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Apple -

In 1976, Apple co-founders Steve Jobs and Steve Wozniak developed their first product, the Apple I, while also working full-time jobs at Atari and HP (respectively).

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Apple -

Despite the refusal of Jobs' boss to invest in the Apple I, the company nonetheless grew quickly. Today it is one of the world's most valuable companies.

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Facebook -

In 2004, Mark Zuckerberg and his friends were inspired to create TheFacebook, a social networking site that was accessible only to Harvard students.

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Facebook -

Soon the site had expanded to other colleges and today Facebook is considered one of the world's main social media platforms. In June 2020, it registered 2.7 billion active users.

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Instagram -

Before he launched Instagram with co-founder Mike Krieger, Kevin Systrom was working as a Product Manager for Nextstop.com by day and building mobile check-in app Burbn by night.

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Instagram -

Having decided that the primary focus of Burbn should be photo-sharing, Systrom and Krieger launched Instagram in 2010. In 2012, Facebook bought the company for US$1 billion.

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Twitter -

It was in 2005 while he was working at podcast platform Odeo that Jack Dorsey created twittr, a site where people could update their status in real time.

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Twitter -

Twittr remained a side hustle until it was renamed 'Twitter' and officially launched in July 2006. To this day, Twitter remains one of the most popular social media platforms.

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Craigslist -

The classified ads website Craigslist started in 1995 as an email that founder Craig Newmark sent to his friends. It highlighted events happening around San Francisco.

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Craigslist -

In 1999, Newmark quit his job to turn Craigslist into a company. It expanded quickly and now covers 70 countries, although the website retains its original, minimalist aesthetic.

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Groupon -

Before it became Groupon, Andrew Mason's business venture was a web tool called The Point. Founded in 2006, the tool's aim was to bring people together to achieve a common goal.

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Groupon -

In November 2008, The Point became Groupon, a site dedicated to offering group discounts. By October 2010, Groupon was available in 250 cities and had 35 million registered users.

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Imgur -

Imgur creator Alan Schaaf was studying at Ohio University when he decided to develop an image uploader to compete with PhotoBucket. Imgur took him a mere two weeks to build.

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Imgur -

In its first year, Imgur had half a million page views each month, and by 2011 Schaaf had moved the business to San Francisco to officially become a company.

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Spanx -

It was while Sara Blakely was getting ready for a night out in the late 1990s that she decided to cut the feet out of her pantyhose and the idea for Spanx was born.

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Spanx -

Once she had a manufacturer on board, work on the prototype began. Spanx the company was founded in 2000, and in 2012 Blakely became the youngest female self-made billionaire.

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Under Armour -

The idea for the product that would eventually be sold under the brand Under Armour first came to founder Kevin Plank when he was a college football player fed up with his sweaty shirts.

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Under Armour -

He developed a shirt that would not absorb sweat and sent it to NFL players. Nowadays, Under Armour is a market leader and in 2019 it had a revenue of US$5.3 billion.

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Yankee Candle -

As a teenager in 1969, Yankee Candle founder Mike Kittredge made a candle for his mom. The product was so popular with the neighbors that he began to sell the candles from his garage.

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Yankee Candle -

Four years later, Yankee Candle moved into a paper mill in Massachusetts and in 1998 the company was sold for a whopping US$500 million. Today it has over 500 stores worldwide.

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WeWork -

WeWork founder Adam Neumann was heading up baby clothing company Krawlers, when he and architect Miguel McKelvey noticed that their office building had several vacant spaces.

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WeWork -

Initially the duo launched Green Desk, which rented out the spaces in that building. WeWork was then born in 2011. In 2019, it had a revenue of US$3.5 billion.

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TheSkimm -

Media company TheSkimm is the result of Carly Zakin and Danielle Weisberg's shared passion for disseminating news. The idea started as a curated news list to send to people's email inboxes.

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TheSkimm -

With no investment and just US$4,000 between them, the credit card debt soon racked up. But with their first email everything changed, and TheSkimm now has over seven million subscribers.

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Nasty Gal -

In 2006, Sophia Amoruso launched the San Francisco-based eBay site Nasty Gal. With a name inspired by Betty Davis, the site sold vintage fashion items.

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Nasty Gal -

Having spent its early days as an online  operation, Nasty Gal occupied its first warehouse space in 2009. By 2012, it was named "Fastest Growing Retailer" by INC Magazine.

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The Khan Academy -

The Khan Academy founder Sal Khan had a day job at a hedge fund when he first started tutoring his cousin online in 2004. Quickly more family members came to demand his services.

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The Khan Academy -

In 2009, he quit his job to focus on the project full time. The Khan Academy has since received a US$1.5 million donation from the Bill & Melinda Gates Foundation.

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OculusVR -

OculusVR's co-founder Palmer Luckey built the virtual reality glasses from his garage. He was studying journalism and working as an engineer at the time.

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OculusVR -

Eventually Luckey dropped out of college to focus on his side project full time. OculusVR raised US$2.4 million on Kickstarter and was bought for $2 billion in 2014.

(Business Insider) (The Balance SMB)

See also: How much do tech companies really know about your children?

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