- Many of America's longtime top CEOs have held their positions for years.
- They've weathered their companies going public, internal turmoil, and public scandals.
- Tech execs like Facebook'sMark Zuckerberg and Amazon'sJeff Bezos were once fresh faces on the scene.
- Now, they've crafted themselves into multibillionaires while growing their businesses into worldwide success stories.
- Take a look at how dramatically these longtime top execs have changed since they've started the job.
- Visit Business Insider's homepage for more stories.
Any time Mark Zuckerberg mentions Facebook, he often brings up how he started it in his dorm room at Harvard when he was just 20 years old.
Early photos of Zuckerberg show him in a plain T-shirt, sweats, and Adidas sandals lounging on the steps of his would-be alma mater. Although Zuckerberg's wardrobe hasn't changed much (albeit the slides and sweats), the company he founded has.
Today, Facebook has more than 2.4 billion users and has fought to keep its reputability as privacy scandals continue to plague the social network and Zuckerberg himself.
Take a look at how dramatically Zuckerberg and 13 other world-famous CEOs have changed over the course of their job.
Marissa Perino contributed to an earlier version of this article.
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Jeff Bezos founded Amazon when he was 30 in 1994. Like other famed tech execs, he started the company in his garage in Seattle.
Before Amazon, Bezos was a senior vice president at D. E. Shaw, a hedge fund, until 1993 when he decided to begin selling books on the internet.
In the first month of its launch, Amazon sold books to people in all 50 states and in 45 different countries. And it continued to grow. Amazon went public on May 15, 1997.
Fast forward to the end of 2019, and Bezos, 55, is the second-richest person on the planet, with a net worth of $110 billion.
In September 2018, Amazon briefly became the second US company to achieve a valuation of more than $1 trillion.
Much of Bezos' wealth comes not from his salary but from the Amazon shares he owns. Bezos currently holds more than 57 million shares in Amazon, accounting for a roughly 12% ownership stake.
Mark Zuckerberg founded "The Facebook" when he was 20 years old in 2004 while studying at Harvard University.
He then dropped out of school after his sophomore year to focus on the social network full-time. Facebook raised its $12.7 million Series A round of funding while he was barely of legal drinking age.
Time magazine named him "Person of the Year" just six years later, while Facebook's initial public offering in 2012 was the biggest-ever technology IPO at the time.
Zuckerberg, now 35, has a net worth of $75.6 billion.
Today, Facebook has more monthly active users than any single country in the world has people — 2.4 billion.
However, for the last few years, Facebook has faced scandal after scandal. It's been called out on multiple occasions for the way it handles user data. Zuckerberg testified for 10 hours in front of Congress last April over the Cambridge Analytica data-harvesting scandal.
Facebook has also been the center of debates regarding how to regulate when tech companies that have too much power.
Steve Jobs and Steve Wozniak started Apple Computer Company in 1976 in Jobs' garage. Jobs was just 21.
Jobs was historically the brains behind Apple, while Wozniak was the engineer. In 1984, Apple released its first personal computer, the Macintosh.
Jobs famously left (or was ousted, depending on who you believe) in 1985, after clashing with CEO John Sculley. Twelve years later, Apple bought Jobs' startup NeXT Computer, bringing him back into the fold.
Jobs ushered in a new era at Apple, introducing the iPhone and iPad. In 2003, he was diagnosed with a unique form of pancreatic cancer.
In August of 2011, Jobs handed the CEO reins to Tim Cook and went on medical leave. In October 2011, he died at 56.
According to Forbes, in 2007, Jobs' net worth was about $7 billion at the time of his death.
Today, Apple is one of the most valuable companies in the world, with a market valuation at roughly $1.2 trillion.
Jobs named Tim Cook, then 51, the COO of Apple in 2007, the same year the iPhone was released. Jobs noticed Cook's leadership quickly, and handed off the CEO title to Cook in 2011.
Jobs is held up as one of the greatest CEOs in history. There was a lot of uncertainty over whether or not Apple could keep the momentum going under Cook.
In 2015, Cook pioneered and released the Apple Watch, the company's first entirely new product in the post-Jobs era.
Today, Apple is worth $1.2 trillion under Cook, now 59.
The company was worth about $330 billion at the time that Jobs died.
In January 2019, after Apple missed its holiday sales targets, Cook said the company's biggest long-term project is to break into consumer health, signaling the CEO's plans to make Apple irreplaceable in the lives of its costumers.
Bill Gates and Paul Allen founded Microsoft in 1975. Gates was just 20 years old, and like Zuckerberg, he dropped out of Harvard to spend more time with his technology startup.
Gates and Allen met in high school, when both were obsessed with computers and software. They built Microsoft from a company that just designed and sold software, into one that sells its own consumer electronics, operating suites, and personal computers.
Allen died in 2018 at the age of 65 after a battle with Non-Hodgkin's Lymphoma.
Today, Gates, 64, is the richest man in the world, with a net worth of $112 billion.
Gates had lost the title of world's richest person to Jeff Bezos in 2017, but in November 2019 he regained that status.
Gates gives a large chunk of his fortune away to charity alongside his wife, Melinda, with their foundation, the Bill & Melinda Gates Foundation — the largest private foundation in the world. Gates has not worked at Microsoft since 2008.
Larry Page and Sergey Brin founded Google in 1998 when they were both 25 years old.
The two founded Google in a garage in Menlo Park, California. They met when Page was touring Stanford University in 1995. Both soon thereafter dropped out of Stanford.
Google, the catalog of "every link on the internet," is now the world's most-used search engine. The company has also branched out significantly: It spans video content, mobile technology, education, digital libraries, and even self-driving cars.
Page, now 46, is the seventh-richest person in the world with a net worth of $65.4 billion. In December 2019, he stepped down as CEO of Alphabet, Google's parent company.
Both Page and Brin announced they were stepping down from their leadership roles at the company in a letter that announced Google CEO Sundar Pichai will be CEO of both Google and Alphabet moving forward.
Brin, now 46, is just behind Page in terms of net worth, at $63.4 billion.
Brin was the president of Google parent company Alphabet until stepping down in December 2019.
He's been known to live luxuriously— he owns the world's fastest yacht — and is reportedly a fan of Tesla.
Jack Dorsey founded Twitter with Ev Williams in 2006 when he was 30.
Dorsey was later ousted from Twitter, the micro-blogging site he thought up, going on to start Square, the mobile payments platform, in 2009.
Dorsey, now 43, was renamed the CEO of Twitter in 2015.
Today, the company has more than 321 million monthly users and took in $909 million last year. Dorsey himself has a net worth of about $5 billion.
His startup Square, on the other hand, was valued at $3 billion at its IPO in 2015 and today has a valuation of $29.6 billion.
Dorsey announced in November 2019 that he would be moving to Africa for at least three months in 2020.
Evan Spiegel founded Snapchat with Reggie Brown and Bobby Murphy in 2011 when he was 21 years old.
Soon after, Spiegel dropped out of Stanford University to work on Snapchat full time.
Tim Cook ended up becoming an early Snapchat investor because he was so impressed with Spiegel. Spiegel also famously rebuffed a $3 billion offer from Facebook CEO Mark Zuckerberg in 2013.
Today, Spiegel is 29 and one of the youngest billionaires in the world. His net worth is about $3.3 billion.
In 2017, he was given an $800 million bonus for taking his company, Snap Inc., public at a $33 billion valuation.
Spiegel is married to model and entrepreneur Miranda Kerr, and the couple welcomed their first child — a baby boy named Hart — in 2018.
In 2004, Elon Musk, then 33, made the first of what would be $70 million of total investments in Tesla, an electric car company cofounded by veteran startup exec Martin Eberhard.
By then, Musk, already a multimillionaire, had a long history of founding and funding various tech startups like SpaceX and PayPal.
Musk took an active product role at Tesla, helping develop its first car, the Roadster. The all-electric Roadster launched in 2006, when Musk was serving as Tesla's chairman.
He was named the CEO of Tesla in 2008 after investing in the company with his own money.
When Tesla went public in 2010, it raised $226 million in the IPO, becoming the first car company to go public since Ford in 1956.
Musk, now 48, is worth $26.3 billion — even though he doesn't take a salary from Tesla.
In January 2019, Tesla announced it would pay Musk nothing for the next 10 years — no salary, bonuses, or stock — until the company reaches a $100 billion market cap.
In the more than 11 years since Musk was named CEO of Tesla, he's since made hefty investments in autopilot, the company's self-driving car technology.
Tesla's "autopilot" system is available on all three of its models, including the new Model 3 — a lower-cost car launched in early 2017 that brings the company closer to its goal of making electric vehicles that are affordable for the masses.
One Wall Street firm thinks Tesla stock will surge 25% in 2020.
Larry Ellison co-founded Oracle, the software firm, in 1977 when he was 33 years old. He said he started the company because he saw a gap in management databases.
As one of the key drivers of the growing computer industry, Oracle grew fast. In 1986, Oracle had its initial public offering, reporting revenue of $55 million.
Ellison, now 75, gave up the CEO role at Oracle in 2014. Bloomberg pegs his net worth at about $59.5 billion.
And although he no longer heads the company he founded, Ellison still sits as Oracle's chairman of the board and chief technology officer.
Satya Nadella joined Microsoft in 1992 at age 25, when founder Bill Gates was still the reigning CEO.
After several vice president positions, Nadella was named president of the Server and Tools Division before he finally ascended to the CEO role in 2014.
Nadella is only the company's third CEO, following Steve Ballmer and Bill Gates.
Under his leadership, Microsoft has acquired big-name companies such as LinkedIn and GitHub, enjoyed rising stock, and is once again considered a major threat to Apple.
Hailed as one of the world's most powerful women, Meg Whitman first worked for companies P&G and Hasbro before she became CEO of eBay in 1998.
Whitman stayed at eBay for 10 years and left the company in 2008 as a billionaire.
After joining Hewlett Packard's board in 2011, Whitman was offered the CEO position.
Whitman, now 63, announced in 2018 she would leave HP after seven years and take up her third CEO position in 2018 at Quibi, Jeffrey Katzenberg's (DreamWorks co-founder) mobile-video startup.
Now 63, she's worth $3.7 billion, according to Forbes.
Michael S. Dell officially founded his company under the name PC's Limited in 1984.
Under its new name, Dell Computer Corp., the company went public in 1988 and a few years later, at age 27, Dell became the youngest CEO ever to lead a Fortune 500 company.
After several years in a chairman position, Dell returned to his CEO role in 2007 and has continued to head the company ever since.
Dell now has a net worth of $30.1 billion, making him the 29th-richest person in the world.