Marc Andreessen co-authored Mosaic in 1993, the first web browser to display inline images, a development that triggered a 342,000 percent increase in web traffic over the following year. This software shift transformed the internet from a niche academic tool into a widely accessible global medium, laying the foundation for modern commercial web interaction.
Early Programming and Education
Born in 1971 in Cedar Falls, Iowa, Andreessen attended New Lisbon High School before enrolling at the University of Illinois Urbana-Champaign. While studying computer science, he held a student programmer position at the National Center for Supercomputing Applications, where he earned $6.85 per hour. He also completed two internships at IBM in Austin, Texas, working on AIX graphics software and 3D language APIs, which provided the technical background necessary to address the complexities of early World Wide Web browsers.
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Working alongside Eric Bina, Andreessen developed Mosaic to simplify web navigation and ensure compatibility across various computing platforms. Following his departure from the University of Illinois in 1994, he moved to California and co-founded Mosaic Communications Corporation with Jim Clark. The company later rebranded as Netscape Communications, introducing Netscape Navigator to the public. After the firm went public in 1995, it was eventually sold to AOL in 1999 for $4.3 billion, with Andreessen serving as chief technical officer.
Enterprise Software and Venture Capital
After the AOL acquisition, Andreessen co-founded Opsware, originally named Loudcloud, with Ben Horowitz, Tim Howes, and In Sik Rhee. The company provided hosting and infrastructure services before Hewlett-Packard acquired it for $1.6 billion in 2007. In 2009, he co-founded the venture capital firm Andreessen Horowitz. The firm managed $2.7 billion within three years and has since expanded into diverse sectors including cryptocurrency, blockchain, and national interest initiatives such as defense and robotics through its American Dynamism fund.
Fast facts
- Born: 1971, Cedar Falls
- Education: University of Illinois Urbana-Champaign
- Notable work: Mosaic
- Co-founded: Netscape (1994)
- Firm: Andreessen Horowitz (2009)
- Award: Internet Hall of Fame (2013)
- Award: Queen Elizabeth Prize for Engineering (2013)
- Citizenship: United States
Questions readers ask
What was the significance of the Mosaic browser?
Mosaic was the first widely used web browser to integrate images directly into pages, which facilitated a massive expansion in internet usage and accessibility.
What is the primary focus of Andreessen Horowitz today?
The firm invests in various technology sectors, including cryptocurrency, blockchain, and American Dynamism, which covers defense, aerospace, and advanced manufacturing.
Achievements
- Internet Hall of Fame — 2013
- Notable work: Mosaic
- Notable work: Fairshake
- Affiliated with Andreessen Horowitz and Netscape
- Educated at University of Illinois Urbana-Champaign and New Lisbon High School
- Worked as computer scientist, entrepreneur and inventor
