captioning funded by cbs and ford-- built for the road ahead. >> stahl: the "costa concordia" is a resting carcass sitting precariously on two underwater mountain peaks, the swimming pools and jacuzzis where passengers sunbathed and sipped cocktails, now empty and askew. and below, ghostly vestiges of the contents litter the floor on what italian authorities have designated an official crime scene. 30 people died, two are still missing. so, how are they going to raise it? that's our story tonight.

>> gupta: it all started in 2004 when sal khan was working as a hedge fund analyst in boston and his cousin nadia, a seventh grader in new orleans, was struggling with algebra. he agreed to tutor her remotely, and wound up posting lessons on youtube. but then an odd thing happened-- total strangers started using them, too. >> just like we talked about consumer surplus, this is a producer surplus. >> innovation never comes from the established institutions. it's always a graduate student or a crazy person or somebody with a great vision. sal was that person in education. in my view, he built a platform that could completely change education in america. >> logan: when he was just 29, jack dorsey invented twitter, a technology that changed the way hundreds of millions of people communicate all over the world, from the president to the pope, celebrities, teens and teachers. >> you just take the card and swipe it through. >> logan: seven years later, dorsey heads up a company called square, which promises to revolutionize the way we pay for things.

>> you don't even take your phone out of your pocket. it just pops up on the screen? >> yes. >> logan: and did we mention he wants to be mayor of new york city? >> i'm steve kroft. >> i'm lesley stahl. >> i'm bob simon. >> i'm lara logan. >> i'm sanjay gupta. >> i'm scott pelley. those stories tonight on "60 minutes." break a leg! i used to love hearing that phrase... but not since i learned i have postmenopausal osteoporosis and a high risk for fracture. i want to keep acting but a broken bone could change that. so my doctor and i chose prolia® to reduce my risk of fractures. prolia® is proven to help make bones stronger. i take prolia®. it's different- it's two shots a year. do not take prolia® if you are pregnant, are allergic to it or if you take xgeva® ..prolia® can cause serious side effects, including low blood calcium levels,

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>> stahl: ever since the wreck of the "costa concordia" a year and a half ago, the huge italian luxury liner has been sitting

semi-submerged off the coast of tuscany, looking like a big beached whale. it's the largest passenger ship ever capsized, easily surpassing the "titanic." and, as we reported last year, removing the ship has turned out to be the most complicated, the most expensive, the most daunting and the riskiest salvage operation ever. the "costa concordia" is a rusting carcass, sitting precariously on two underwater mountain peaks. the swimming pools and jacuzzis where passengers sunbathed and sipped cocktails, now empty and askew. a clock remains frozen in time, marking the hour and minute when the ship lost power. and below, ghostly vestiges of the ship's contents litter the ocean floor in what the italian authorities have designated an official crime scene. 30 people died; two are still missing.

>> nick sloane: welcome on board. >> stahl: thank you. nick sloane from south africa is the senior salvage master. he took us out to the wreck site. how big is that ship? >> sloane: she's huge, and what you see at the moment is only 35% of her. so 65% underneath is like an iceberg underneath there. >> stahl: now the plan is to roll the 60,000-ton ship in one piece onto an underwater platform, raise it, and then float it away so it can be cut up for scrap. so, you're planning to rotate a ship that weighs 60,000 tons. >> sloane: yeah. >> stahl: so, let me see. you're going to... this is the ship. you have to do it like... >> sloane: we'll roll it up right. >> stahl: ...the whole thing together at once, creaking. >> sloane: all the way along the three football fields long. >> stahl: three football fields long? >> sloane: yeah. and we're going to rotate it all at the same time. >> stahl: it sounds like an experiment in defying the laws of physics.

the actual work is being shared by nick sloane's titan salvage, an american wreck removal company, and micoperi, an italian engineering firm. sergio girotto is the company's project director, in charge of re-floating a 60,000-ton ship filled with seawater. so you have to create much more buoyancy than even the original weight of the ship because of all the water. >> girotto: absolutely. absolutely. >> stahl: a team of engineers came up with something ingenious: to, in effect, weld a new ship onto the shipwreck. it starts here with the construction of towering steel boxes called "sponsons." they're gigantic. the largest ones weigh 500 tons each and stand 11 stories high, and they'll be outfitted with hoses and sophisticated air pumps to create buoyancy. here's what's supposed to happen-- one by one, nine of them will be welded across the

exposed side of the ship. >> girotto: they will be joined together like a big lego, outside in the open. >> stahl: and they have to be precisely welded, correct? >> girotto: the space from one sponson to the other, it is less than two inches, so they must be fabricated with a very strict tolerance. >> stahl: this row of hydraulic pulleys will tighten a string of 36 cables attached to the sponsons, slowly rolling the ship upright. then, other steel boxes will be welded to the other side of the vessel, and, eventually, the hollow, air-filled sponsons will act like waterwings so the "costa concordia" can be floated and towed away. has this ever been done before? >> girotto: no, no. >> stahl: this is brand new? >> girotto: the brand new technology, brand new methodology. to lift a vessel in this way, it

is the first time ever. >> stahl: and no one's 100% sure lifting a vessel this gigantic in one piece is going to work. it's the biggest passenger ship ever wrecked, twice the size of the "titanic." before the accident, it was a 15-story floating palace big enough to house a small town of 4,000 people. as this promotional video shows, it had 1,500 luxury cabins, 18 restaurants and bars, four swimming pools, five jacuzzis, and a casino. the accident occurred in january of last year, ominously on the night of friday the 13th. nervous passengers crowded together as water gushed in. sailing too close to shore, the ship had struck a huge boulder hidden just beneath the surface. you can see that it just tore

the pipes apart. >> sloane: yeah, the momentum of a large ship like this hitting that rock, she had no chance. >> stahl: almost like a shark eating the belly of a whale or something, it just ate into that. >> sloane: yeah, it was a big rock, about 96 tons. >> stahl: the wreck's an eyesore right off the beaches of tiny giglio island that has been overrun by an armada of support vessels and an army of welders, crane operators, and marine engineers. because of the angle of the ship, the workers have to take a four-day course in mountain climbing. here, they're working on the strong cables that are keeping the ship in place. much of the work is being done underwater by specially trained salvage divers, 111 in all. ebano, who's from brazil, is being geared up and safety- checked by other divers on his team. >> sloane: he's got communication for talking. he's got the air. he's got back-up air.

he's got a camera and a light. >> stahl: every one who goes in has a support team of at least five up on deck. once suited up, ebano is lowered down in a cage. the day we were there, the divers were ratcheting, tightening, measuring those massive steel cables that run under and around the ship to tie it down so it doesn't slide off the mountain peaks and sink. it's an exacting and dangerous job, so teammates stand by on deck in case of an emergency, and a dive supervisor monitors and directs the action. >> duane morsner: do you want to move back on your... on your camera and give us a wide shot of exactly what's going on down there. >> stahl: duane "monster" morsner oversees a dive team. so you're just watching everything he does, listening to him? >> morsner: and explaining to him exactly where to go because sometimes when you go past 30 meters, you can get narcosis and it sort of affects your-- your thinking.

and obviously, if he's in trouble, i can see what the problems are and help him out and check his depth, that sort of thing. >> stahl: there's a salvage divers' camaraderie. they live in close quarters in floating barracks next to the ship. and while they come from eight different countries, speaking different languages, they're like soldiers in combat-- they have each others' back. >> morsner: move towards the bow of the "costa concordia," please. >> stahl: though these divers are in the water round the clock, each one can stay under no longer than 45 minutes at a time. they have five minutes to get from a depth of 40 feet into a decompression chamber. when a diver surfaces, it's a race to strip off his gear and get into the chamber. the divers and everyone else work 'round the clock, seven

days and nights a week, in a race against time. they have to remove the ship before storms like this one last winter break it apart. >> sloane: every storm weakens the structure, and there will be a certain point where the structure... and she will just say, "i've had enough." >> stahl: so is that what has you worried the most, the weather? >> sloane: yeah, yeah. when you have bad weather, you don't sleep. >> stahl: neither do the insurance companies that are footing the bill. so, how much is this operation costing? >> sloane: well, basically, it's going to be around about $400 million, plus or minus, and that's a lot of money. >> stahl: did your company ever consider proposing just blowing it up? because i know a lot of salvage operations, they just dynamite. >> sloane: yeah, some places in the world, that would be a solution. in this scenario, i don't think it would ever be allowed. >> stahl: is the reason because this is such a tourist area? >> sloane: oh, the environment is the number one priority. >> stahl: number one. that's because the ship settled in a nationally protected marine

park and coral reef that's home to dolphins, exotic fish, these huge rare mussels, and more than 700 other botanical and animal species. sergio! >> girotto: hi, lesley. >> stahl: sergio girotto took us to one of six shipyards in italy that have been pressed into action. at this one north of venice, they're building this huge steel platform. it's one of six platforms that'll be lowered into the water, its legs anchored into the hard granite sea floor. when the ship is rolled upright, it will roll onto them. so the ship is over there? and what, it's going to roll...? >> girotto: yeah, it's going to rotate, and rotate slowly to rest on this platform, exactly the same area where we are standing. >> stahl: the platforms are necessary to keep the 60,000-ton ship from sliding off its mountain peaks, down into the

abyss. but getting the platforms to the wreck site is an operation in and of itself. >> girotto: and we make the tour of italy. >> stahl: they will be floated by barge from the shipyard to the shipwreck off giglio island. around the heel, around the toe and up to giglio. >> girotto: up to giglio. it is a long trip. >> stahl: how long? >> girotto: it's going to take... it's going to take 15 days. i tell you, it is a gigantic project. if you simply think of the quantity of steel, it is three times the weight of the tower eiffel. >> stahl: of the eiffel tower? >> girotto: exactly. three times the weight of the tower. >> stahl: out at the wreck site, they're lowering giant pipes that are used to drill holes in the seabed for the legs of those massive platforms. so these are these big pipes that you're putting down. to protect the environment, the drill bit will be enclosed in

the pipe in order to contain any debris from the digging. wow, look how huge! >> sloane: as you can see, this is about eight feet. >> stahl: eight feet is the diameter of the legs of those platforms, and the holes for the legs have to line up almost perfectly. when you put the platforms down, what's your margin of error? >> sloane: the error that we can allow is less than six inches between them. so, if we are more than six inches out, the platforms aren't going to fit. >> stahl: has there ever been a salvage project this big? >> sloane: no, this is-- with the complexities and the amount of engineering, the scale of the equipment that we're bringing in, the size of the teams, this is by far the largest that's ever been done. >> stahl: in the history of salvage? >> sloane: in the history of salvage. >> stahl: let's talk about the day that you are going to rotate the ship onto the platforms. if something's not going right, can you stop it? >> sloane: no, you can't stop it.

you have one chance. >> stahl: one chance? >> sloane: one chance. once you start, you have to finish. >> stahl: we've spoken to arine engineers. they think you have a 50/50 chance. >> sloane: no, it's more than 50/50, for sure. >> stahl: it is? >> sloane: basically, we've got a large engineering team. we have over 200 engineering documents, and everything proves that it can be done, so... >> stahl: on a computer? >> sloane: yeah, on a computer. some parts of the ship will collapse internally. it's going to be very noisy. there's going to be a lot of creaking, groaning, steel snapping. but she'll come upright. >> stahl: steel snapping? >> sloane: yeah. >> stahl: that doesn't sound good. >> sloane: yeah, well, there will be smaller bits of steel, but the larger structure will take it. >> stahl: is there a plan b? >> sloane: we have plan b and c, but we don't want to get there. >> stahl: "there" is cutting up the ship in place, which would be an environmental catastrophe. they'll put plan "a" into effect later this month, when they attempt to raise the ship, under the watchful eyes of the insurance companies, the italian authorities, and camera crews from around the world should

they succeed, the "costa concordia" will then be towed to a dry dock and cut up for scrap. there's so much ship, that process will take two years. and now, the price tag is approaching $900 million. >> go to 60minutesovertime.com to see how the "60 minutes" team managed to get these shots of the "costa concordia." sponsored by viagra. ♪ [ alarm sound for malfunctioning printer ] [ male announcer ] you've reached the age where you've learned a thing or two. [ metal clanks ] ♪ this is the age of knowing what you're made of. so why let erectile dysfunction get in your way? [ gears whirring ] talk to your doctor about viagra. 20 million men already have. ask your doctor if your heart is healthy enough for sex. do not take viagra if you take nitrates for chest pain;

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geico, see how much you could save. >> kroft: now, cnn's sanjay gupta on assignment for "60 minutes." >> gupta: take a moment and remember your favorite teacher. now, imagine that teacher could reach, not 30 kids in a classroom, but millions of students all over the world.

as we first reported last year, that's exactly what sal khan is doing on his web site, khan academy. with digital lessons and simple exercises, he is determined to transform how we learn at every level. one of his most famous pupils, bill gates, says khan-- this "teacher to the world"-- is giving us all a glimpse of the future of education. 36-year-old sal khan may look like a bicycle messenger, but with three degrees from m.i.t. and an m.b.a. from harvard, his errand is intensely intellectual. in his tiny office above a tea shop in silicon valley, he settles in to do what he's done thousands of times before. >> sal khan: we've talked a lot now about the demand curve and consumer surplus. now, let's think about the supply curve. >> gupta: he's recording a ten- minute economics lesson. it's so simple-- all you hear is his voice, and all you see is his colorful sketches on a digital blackboard. >> khan: in this video, we are going to talk about the "law of demand."

>> gupta: when khan finishes the lecture, he uploads it to his web site, where it joins the more than 3,000 other lessons he's done. in just a couple of years, he's gone from having a few hundred pupils to more than six million every month. has it sunk in to you that you are probably the most watched teacher in the world now? >> khan: i... you know, i try not to say things like that to myself. you don't want to think about it too much because it can, i think, paralyze you a little bit. so, if we get rid of the percent sign, we move the decimal over... >> gupta: he's amassed a library of math lectures... >> khan: 12 + 4 is 16... >> gupta: ...starting with basic addition, and building all the way through advanced calculus. >> khan: we are taking limited delta x approach to zero. it's the exact same thing. >> gupta: but he's not just a math wiz-- he has this uncanny ability to break down even the most complicated subjects, including physics, biology, astronomy, history, medicine. how much reading do you do ahead of time? >> khan: it depends what i'm doing. if i'm doing something that i haven't visited for a long time, you know, since high school,

i'll go buy five textbooks in it, and i'll try to read every textbook. i'll read whatever i can find on the internet. let's talk about one of the most important biological processes... >> gupta: sal khan has tackled so many subjects that, if you watched just one of his lectures a day, it would take over eight years to cover it all. >> khan: these are huge time scales... magnetic north is kind of the geographical... and let's say this is point "x" is equal to... basic introduction... light... if this does not blow your mind, you have no emotion. >> gupta: did you ever think about putting yourself visually in the video? >> khan: look, if there's a human face there, especially a funny-looking human face, then it's actually hard to focus on the math. 4,000 is 2,000 x 3 is 6,000. i don't have to shave, i don't have to comb my hair. i just press "record," make a video. there might be spinach in my teeth. who cares? >> gupta: the format is so simple. why does it appeal to so many people? >> khan: i've gotten a lot of feedback that it really does feel like i... i'm sitting next to the person and we're looking at the paper together. let me take out my trusty calculator out. i'm 95% of the time working

through that problem real-time, or i'm thinking it through myself if i'm explaining something. and to see that it is actually sometimes a messy process-- that, you know, it isn't always this clean process where you just know the answer. i think that's what people like, the kind of humanity there. >> gupta: it all started in 2004 when sal khan was working as a hedge fund analyst in boston, and his cousin nadia, a seventh grader in new orleans, was struggling with algebra. he agreed to tutor her remotely, and wound up posting lessons on youtube. they helped nadia, but then an odd thing happened-- total strangers started using them, too. >> khan: i started getting feedback like, you know, "my child has dyslexia, and this is the only thing that's getting into him." i got letters from people saying, you know, "we're... we're praying for you and your family." that's pretty heady stuff. people don't say that type of stuff to a hedge fund analyst, normally. ( laughs ) >> gupta: so, in 2009, khan quit his job and, working from a desk set up in his closet, devoted himself full-time to khan academy. it's a non-profit with a simple

but audacious mission-- "to provide a free, world-class education for anyone anywhere." if that goal sounds far-fetched for a guy working in his closet, consider what happened next. >> bill gates: there's a web site that i've just been using with my kids recently called khan academy-- k-h-a-n. just one guy doing some unbelievable 15-minute tutorials. >> khan: i was like, "those are just for nadia, not bill gates. i have to... i have to look... i have to take a second look at some of this stuff." >> gupta: that's right-- bill gates, one of the smartest and richest men in the world, was using sal khan's free videos to teach his own kids. >> khan: two weeks later, i got a call from... from larry cohen, who is bill gates' chief of staff. and he says, you know, "you might have heard bill's a fan." and i'm, like, shaking. i'm like, "yeah, i heard," you know. and he... and he was like, "if you have time, you know, love to fly you up to seattle." and then, i was looking at my calendar right then for the month-- completely blank. and i was like, "yeah, you know, i think i could, you know, fly in, you know, between, like, laundry and a bath." ( laughs ) "and meet with bill."

>> gupta: that was just three years ago. today, with the help of more than $35 million in funding, much of it from the gates foundation and google, khan has been able to hire, with competitive salaries, some of the most talented engineers and designers in the country. the khan academy office has the intense vibe of a silicon valley start-up. the team is working to create software they hope will transform how math is taught in american classrooms. >> and once they've done all of these, they really understand proper fractions. >> khan: right, right. >> gupta: last year, we visited a class in the los altos school district outside san francisco, where the new khan academy software is being piloted. >> courtney cadwell: grab your computer, log in, and then open "khan academy." >> gupta: right away, you notice something different. there are no textbooks and no teacher lecturing at the blackboard. instead, students watch khan videos at home the night before to learn a concept. then, they come to class the next day and do problem sets called modules to make sure they understand.

if they get stuck, they can get one-on-one help from the teacher-- less lecturing, more interaction. what you think of as homework you do at school, and school work you do at home. it's called "flipping the classroom," and seventh grader laurine forget says using khan academy at home has given her math a big boost. >> laurine forget: i'm not a big fan of textbooks. i thought that khan academy was a lot easier, because it's on a screen, it's easy to find the concept you want to do. >> gupta: and now, with the videos, do you find yourself rewinding it, playing it again if you need to? >> forget: a lot, yeah. >> gupta: do that at home? >> forget: yeah. usually when i watch the videos, it's because i'm having trouble on the practices. so if i don't understand the video, i can always rewind it or pause it so that i can go back to the module and do what i learned. >> gupta: but what's the hardest part about learning this way? >> forget: i don't really think there is a hard part. >> gupta: even kids who don't have a computer at home can "flip the classroom." eastside prep in east palo alto

keeps its computer labs open until 10:00 p.m. so kids like sixth grader alex hernandez can take as much time as they need to learn a concept. >> alex hernandez: my mom, she went to school in mexico. some things she can explain to me, but some, like, she can't. so, like, i take long to, like, try to finish my homework. >> gupta: how did you used to do in math? >> hernandez: pretty bad. like, at a third-grade level math. so, you know, khan academy has helped me. it's like... it's, like, opened doors that i couldn't open. it's helped me a lot. >> gupta: a lot of people have talked about the idea that flipping the classroom is... is sort of what's happening here. you take a little bit of issue with that. >> khan: i kind of view that as... as a step in the direction. the ideal direction is using something like khan academy for every student to work at their own pace, to master concepts before moving on. and then, the teacher, using khan academy as a tool, so that you can have a room of 20 or 30 kids all working on different things, but you can still kind of administrate that chaos. >> gupta: khan academy has created a dashboard so teachers like courtney cadwell can monitor each student's progress.

so, right now, they're all working on things, and you can see that real-time? >> cadwell: yes. >> gupta: so, as you sit here and look at the dashboard, you see how the students are doing individually, you can see how they're doing as a whole class, and you can figure out who you need to help? >> cadwell: exactly. and here, i can track their progress over time. i can see who's rushing ahead, who's lagging behind. i can see if they begin to stagnate. >> gupta: a blue bar indicates a student knows a concept; orange, they're still working on it. but if a red bar pops up... >> cadwell: it's kind of the red flag to tell me, "hey, it's time to step in and intervene." and i can see... >> gupta: oh, so you can see not only it's red, but specifically what the problem is. >> cadwell: what they missed. and you can see the number of seconds they spent on each problem. i feel like i'm using my time more effectively with my students because, instead of making the assumption that the entire class is weak in this area and i need to spend time reviewing this, i can really pull those three, four, five kids, do a mini-workshop,

address those needs, and allow those other students to move on to problem-solving activities, or project-based learning with their peers. >> gupta: so far, the national education association has supported non-profit technology like khan academy in the classroom, as long as teachers are trained properly. but as with any new innovation, khan says there are always some skeptics. >> khan: i've seen some subset of teachers who say, "oh, what is this video thing?" you know, "live human interaction is important." and the reason why that... that bothers me a little bit is that i know that's exactly what we're saying. in fact, we exactly agree with you, that what we're trying to do is take the passivity out of the classroom so that you, as a teacher, will have more flexibility. >> gupta: does it minimize the role of the teacher? does it make it less impactful? >> khan: no, i think it's the exact opposite. we kind of view teachers playing the role of more like a coach or a mentor, which, once again, i personally believe is a much higher value thing than a lecturer. >> gupta: khan academy's math program is being piloted in 50 schools, mostly in california. preliminary test scores from a handful of classrooms have shown improvements, especially for students who were struggling.

in the meantime, chief operating officer shantanu sinha says they're now gathering massive amounts of data-- not just from american classrooms, but from every khan academy user around the world. so, you can see how many problems were done over the last 24 hours? how many was it? >> shantanu sinha: right now, in the last 24 hours, we had close to 1.8 million. >> gupta: wow. not total, but just one day? >> sinha: yeah. yeah, just in... in a 24-hour period. >> gupta: and when you take a look at total users over the last 18 months... >> sinha: 41 million visits from the united states. we can look in-- from india, 1.7 million; australia, 1.4 million. >> gupta: right. it is pretty amazing to think that millions of people all over the world are using khan academy right now. >> sinha: yeah. it's a gold mine on how to understand, you know, what... what paths through learning are most effective. >> gupta: khan says they look at all that data and constantly make changes to their software platform. >> khan: we can start fine- tuning things the way that amazon might fine-tune the button to help you buy that book or find the book that you want,

or netflix says, "what's the right movie for you?" we now get to do with education. >> gupta: eric schmidt, the pioneering chairman of google, says he's seen a lot of failed attempts to integrate technology into education, but says what sal khan is doing is different. >> eric schmidt: many, many people think they're doing something new, but they're not really changing the approach, which, with sal, he said, "what we're going to do is not only we're going to make these interesting ten-minute videos, but we're going to measure whether it works or not." >> gupta: he was the guy to sort of make this happen? why do you think it was him and not some person who was an educator or who had a background in this area? >> schmidt: innovation never comes from the established institutions. it's always a graduate student or a crazy person or somebody with a great vision. sal is that person in education, in my view. he built a platform. if that platform works, that platform could completely change education in america. >> khan: 17 over 9 is equal to 1.88. >> gupta: inside classrooms, it's just khan academy math for

now, but sal khan believes his strategy can be used to teach subjects like history and science. and not just in elementary schools, but high schools and even colleges. but no matter how big or how successful khan academy gets, sal khan promises he'll never put a price tag on it. >> khan: the for-profits have to mold themselves much more to the education establishment than we do. as a not-for-profit, we're just like, "what's our mission?" to educate children as well as possible. i've said it enough times, and it's in our mission statement-- a free, world-class education for anyone anywhere. >> gupta: and that's what sixth grader alex hernandez says he needs. has anyone in your family ever gone to college? >> hernandez: no. >> gupta: so it's a pretty big deal for you? do you think you're going to be able to do it? >> hernandez: with help or, like, with more, like, studying or, like, khan academy, i think i can get there. >> gupta: i think you can, too. >> now a cbs sports update. good evening. i'm at the national tennis

center in new york where day seven of the u.s. open saw the defending champions advance. top-seeded serena williams won in straight sets to advance to the quarterfinals and avenge an earlier loss at the australian open. andy murray rolled past florian meyer. live coverage begins tomorrow on cbs at 11:00 eastern time. go to cbssports.com for more sports news and information. to go to college -- sas and we'll help out with the school of your choice." well, i got the grades and, with dad's planning and a lot of hard work, i'm graduating today with a degree in marine biology. i'm so thankful and excited about the future. [ male announcer ] for strategies on how to help your family achieve financial success, visit pacificlife.com. on how to help your family achieve financial success, [ male announcer ] let's go places. but let's be ready. ♪

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>> logan: jack dorsey is one of the biggest and most ambitious innovators of our time. his name doesn't resonate like jobs or bezos or zuckerberg, but his innovations do. and his low profile may have a lot to do with his personality. dorsey describes himself as extraordinarily reserved and shy, which is ironic considering

he's the man who created twitter and changed the way people communicate around the world. then he created a company called square, which is helping to transform the way we pay for things. when we first told you about jack dorsey last spring, square was a start-up. now, it's an international company, but jack dorsey already has his eye on the next job he wants-- mayor of new york city, an unlikely role for a man who calls himself a loner and spends a lot of time dreaming and thinking. "forbes" magazine said you're more of a nerd than steve jobs. >> jack dorsey: which i found insulting. ( laughter ) i'm more of a nerd than steve jobs. i-- i think the reference was because i was a programmer. so, if that is the nerdy way, then guilty. i'm a nerd. >> logan: many believe jack dorsey is the intellectual

successor to jobs. he created the code for twitter with messages that, unlike emails, can be read by anyone in the world. twitter is so instant. it's that moment. >> dorsey: yeah, it's so instant. and now, i get to see the entire world and how they're thinking and how they're feeling and what they're doing and what they care about and where they're going. >> logan: when he created twitter seven years ago, jack dorsey had no idea how big it would become; that 200 million people would be sending more than a billion tweets every three days; that young revolutionaries would use it to help communicate the strategies that fueled the arab spring; that it would force a congressman to resign. twitter has become a marketing tool for hollywood and big business. we use it at "60 minutes." the president tweets. benedict xvi tweeted his final message as pope. what are you most proud of with twitter? >> dorsey: i'm most proud of how quickly people came to it and used it in a million different

ways. they're all over the world, and twitter enables them to take a $5 cell phone and, wherever they are, communicate with the world for free. >> logan: it was a revolutionary new way for people to connect, something dorsey admits he's not very good at in person. what do you think your weaknesses are? >> dorsey: i do have a tendency to really think about things by myself and decide things. >> logan: overthink things. >> dorsey: come out with a decision. i think i can be... i can be silent at some times, which unsettles people a bit because they don't know what i'm thinking. the biggest thing i've learned is that i need to communicate more. i need to be more vocal. >> logan: not communicating well created problems for him at twitter, and jack dorsey, like steve jobs, was forced out of running the company he helped found. were you angry? >> dorsey: yeah. i was... i was angry. i was angry at, you know, the board. i was angry at my cofounders. i was angry at myself.

>> logan: you once described it as being like a... a punch in the guts. >> dorsey: yeah. >> logan: no grudges? you don't hold any grudges? >> dorsey: i'm stubborn, but i don't necessarily hold grudges. >> logan: two and a half years later, new management at twitter invited him back to help run the company, and dorsey accepted. suddenly, he had two jobs. by then, he had dreamed up a new company, square, that he believes can also change the world. he says he runs it differently than twitter. decisions made behind closed doors are sent out immediately on the company's mass email system, including sensitive information on company goals and profits. dorsey roams around the office, available to talk to anyone. do you have an office here? >> dorsey: i don't. i don't have an office. i don't have a desk. >> logan: you don't have a desk at all, even, like... >> dorsey: i don't have a desk. i have my... i have my ipad. >> logan: while twitter is about messages, square is about money. it permits anyone with a smart- phone to become a merchant.

the concept grew out of a brain- rqgd named jim mckelvey, who was both a software ace and a frustrated artist. >> dorsey: he was at an art fair, and he couldn't sell a piece of glass because he couldn't accept a credit card. so, that was, you know, $2,000 lost, and he just got fed up with that. and he came out to san francisco that next week, and we spent the week trying to figure out why no one has done this before. >> logan: and "this," at that moment, was what? >> dorsey: well, we didn't know what it was. it was-- it was a way to accept credit cards on your phone. that's all we knew. >> logan: the software is simple and it's fast, two qualities that are most important to dorsey. to take a payment, you swipe a customer's credit card through a white square that plugs into the earphone jack. >> dorsey: so, you just take the card, you swipe it through. >> logan: the customer signs a receipt electronically. department stores don't use it yet, but millions of small business people do.

>> dorsey: people who are using it to sell things on craigslist to holding garage sales, campaigns. the obama campaign and the romney campaign both used square to raise funds. >> logan: dorsey says merchants like square because the fee is less than some credit cards charge. and business at square is booming, accelerating in four years from zero to $15 billion in annual transactions. jack dorsey started thinking about the software he's built in silicon valley nearly 30 years ago when he was growing up in st. louis. he had a speech impediment as a kid and spent a lot of time alone at home, playing with computers when he was eight. he taught himself how to build computer programs before he was a teenager. dorsey was fascinated by trains and maps, and he used to spend hours down at these train yards. most kids would have pictures of football players and girls on their walls, or their favorite bands. >> dorsey: right. >> logan: and you've got maps.

>> dorsey: i have maps. >> logan: and trains. >> dorsey: yeah. >> logan: studying trains was the beginning of his lifelong obsession to learn how things work in the real world and translating that into the virtual world. young jack was intrigued by the messages he heard coming out of the st. louis emergency dispatch center. at home, he listened to it all on a police scanner, and he was struck by the fact that everyone talked in short bursts of sound, a system of communication that later inspired him to invent twitter. >> dorsey: they're always talking about where they're going, what they're doing and where they currently are. and that is where the idea for twitter came was now we all have these cell phones, we had text messaging, and suddenly we could update where i was, what i'm doing, where i'm going, how i feel. and then, it would go out to the entire world.

>> logan: as a teenager, he created software that tracked the movement of emergency vehicles on a map. then, he tried to get a job with a large dispatch company in new york, but there was no contact information on their web site. >> dorsey: i found a way into-- into the web site. i found a hole. i found a security hole. >> logan: is that-- are you-- is that the same thing as hacking? >> dorsey: it's ha-- yes. ( chuckle ) hacking. hacking is... hacking is... is... >> logan: a crime. >> dorsey: well, no. ( chuckle ) criminal hacking is a crime. hacking is actually a... >> logan: hacking for a job application is not a crime? >> dorsey: no, no, no, no, no. ( chuckle ) no, not a crime at all. and i emailed them, and i said, "you have a security hole, here's how to fix it, and i write dispatch software." >> logan: and they hired you. >> dorsey: and they hired me a week later. and it was a dream come true, which is a weird dream for a kid. >> logan: now the kid who ventured to new york when he was 19 has a new dream-- to expand square globally.

he's moved into canada and japan, and opened an internet shopping site. dorsey knows he'll have some stiff competition. paypal is a competitor of yours. it has a similar system. google, walmart and target are developing their own systems. what prevents the competition from putting you out of business? >> dorsey: well, you know, our take on this is, you can worry about the competition, you can constantly look in your rearview mirror, and you can constantly look around and really not notice the road ahead of you; or you can focus on what's ahead of you and drive... and drive fast, right? and drive within the speed limit, of course, but drive fast. >> logan: but hopefully faster than everyone else. >> dorsey: faster than everyone else. >> logan: to keep his employees motivated and thinking, you won't be surprised to learn that jack dorsey is a bit unconventional. instead of a company picnic or softball game, he took them to a place in san francisco called land's end. he wanted to make them think about the golden gate bridge. why?

>> dorsey: why? because we see the bridge as, like, this perfect intersection between art and engineering. it has pure utility in that people commute on it every single day. >> logan: dorsey's point to his colleagues is that when people look at the bridge, they don't think about the commuters or how it functions; they admire its simplicity and beauty. he thinks good software should work the same way. >> dorsey: when people come to twitter and they want to express something in the world, the technology fades away. it's them writing a simple message and them knowing that people are going to see it. >> logan: and that, to you, is functionality and beauty. >> dorsey: yeah. it disappears. it disappears because it's so intuitive, it just works. >> logan: that's the thinking behind a dorsey invention called square wallet which radically changes the way we pay for things. is this your favorite place to go for coffee? >> dorsey: yeah, it is one of my favorite places. >> logan: to show us how it works, dorsey invited us to visit a cafeé just around the corner from his office.

>> dorsey: what would you like? >> logan: i will have a latte, please. >> waitress: is whole milk okay? >> logan: no. with the help of g.p.s., the barista's ipad knows dorsey and his smart-phone are in the house, and his face shows up on the tablet's screen before he even orders. so, all your customers-- i mean, who have this app-- they just appear. >> waitress: yeah, yeah, it appears. >> logan: it's like a virtual credit card. you don't take your wallet out, you don't even take your phone out of your pocket. >> dorsey: i could. >> logan: it just pops up on the screen. >> dorsey: yeah. >> logan: the receipt shows up in an email. it's seamless and simple, but, like his other invention, twitter, jack dorsey thinks square fundamentally changes how people interact and how they feel. >> dorsey: money touches every single person on this planet, and at one point in their life, they feel bad about it. it feels dirty sometimes. it never feels great. but it does feel great when it disappears. it feels like you're taken care of. it feels like the world is just working.

>> logan: everything seems to be working for jack dorsey. the "wall street journal" magazine named him technology innovator of the year. accepting that award brought him back to new york, a city he fell in love with when he worked for the dispatch company he hacked into. dorsey may spend most of his life in the virtual world, but he's still fascinated by real world systems, and manhattan, with its subways, is the biggest system on earth. it may seem like an unrealistic ambition for such a reserved person, but dorsey not only wants to move here someday, he wants to run for mayor. >> dorsey: what i love about new york is just the electricity i feel right away. i mean, just look at us in this station. there's just people walking everywhere and everyone. >> logan: chaos? >> dorsey: it's chaos. it's kind of like being in a car in the middle of a thunderstorm. everything is raging around you, but you're safe inside that car.

so, new york feels very much to me like that. >> logan: jack dorsey knows it helps to be a billionaire if you run for mayor in new york. it's worked before. but if he's serious about running, and he says he is, it will be interesting to see just how he communicates with the voters. do you find it easier to communicate with people via twitter or face to face? >> dorsey: i guess my natural state would be through mediation of letters or through texts. all those mediums, i definitely find ease with. but do i appreciate as much as face to face communication? no. do i feel like i'm an expert in having a normal conversation face to face? absolutely not. that's just not my natural state. i would rather be walking land's end and thinking about things. >> logan: and tweeting. >> dorsey: and tweeting. ( laughter ) ( telephone rings ) hi, honey. how's the camping trip? well, kids had fun, but i think i slept on a rock.

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