Mosaic and Netscape: The Browsers That Opened the Web to Everyone
NCSA Mosaic put images in web pages in 1993, and Netscape Navigator turned the web into a mass medium. Here is how two browsers changed the internet.
The early web was a tool for scientists. A handful of text-only browsers existed, and the people who used them were mostly at universities and research labs. Two browsers changed that: NCSA Mosaic in 1993, and Netscape Navigator in 1994. Together they turned the web into something that ordinary people wanted to use.
Mosaic at the NCSA
The National Center for Supercomputing Applications (NCSA), at the University of Illinois at Urbana-Champaign, released the first version of Mosaic in early 1993. It was led by Marc Andreessen, who was then an undergraduate student, and Eric Bina, a staff programmer. It was not the first graphical browser, since others such as ViolaWWW and Berners-Lee's own browser existed. But Mosaic had several features that made it a better choice for most people:
- It displayed images inline with the text, instead of opening them in a separate window.
- It was easy to install, with versions for Unix, Windows and the Macintosh.
- It had a clear interface with a back button and clickable links.
Inline images mattered more than they might sound. The web turned from a library of documents into something closer to a magazine, and people started to design pages for the screen. Downloads of Mosaic spread quickly across universities, and press coverage in 1993 and 1994 introduced the word "web" to a wider audience.
Netscape is founded
Andreessen graduated and moved to California. There he met Jim Clark, the founder of Silicon Graphics, and in 1994 they started a company that was first called Mosaic Communications Corporation. After the University of Illinois raised objections about the name, it was renamed Netscape Communications. The company hired several of the Mosaic developers and wrote a new browser from the beginning, without using the NCSA code.
Netscape Navigator was released in late 1994. It was faster than Mosaic, handled images progressively so that pages appeared sooner on slow modems, and was available free of charge for non-commercial use, with a paid licence for businesses. It quickly became the dominant browser.
Innovations that came from Netscape
| Innovation | Why it mattered |
|---|---|
| SSL (Secure Sockets Layer) | Encrypted connections made online shopping and logins safer; it is the ancestor of today's TLS |
| JavaScript | Let pages react to the user; created in 1995 (see our JavaScript article) |
| Cookies | Let sites remember a visitor between page loads, which made shopping carts possible |
| Frames and extensions to HTML | Gave designers more control, but also created compatibility problems |
The IPO that startled Wall Street
Netscape went public in August 1995. The company was barely sixteen months old and had not yet made a profit, but its share price rose sharply on the first day of trading. It is often named as the event that started the public's enthusiasm for internet companies, and it set the stage for the dot-com boom. Whether or not that investor enthusiasm was justified is a separate question, which we discuss in our article on the 2000 bubble.
What happened to both
Mosaic's development at NCSA ended in the mid-1990s. Its code was licensed to other companies, and one of them, Spyglass, supplied the starting point for Microsoft's first Internet Explorer. Netscape's dominance did not last: competition from Internet Explorer, which Microsoft bundled with Windows, reduced its market share through the late 1990s. In 1998 Netscape released its browser source code, creating the Mozilla project, and America Online acquired the company in 1999. The Mozilla code lives on in Firefox.
Speed and the modem era
It is easy to underestimate how much the early browsers were shaped by slow connections. In the mid-1990s most home users connected with dial-up modems, so a single large image could take a long time to appear. Netscape's progressive rendering, where a page appeared piece by piece while it downloaded, was a direct response. The same concern appears today in a different form: visitors on mobile networks leave slow sites, and search engines take loading speed into account. Reducing image sizes, using caching and serving files through a CDN are modern versions of the same optimisation work that Netscape's engineers did in 1994.
The commercial lesson was also clear. Giving the browser away for free did not prevent Netscape from building a large business. It sold server software and tools around the browser, and it benefited from being the standard way to reach the web. Free access to the platform and paid services built on top of it is a model that many later internet companies copied.
Why it matters for site owners
Everything you do on a website is shaped by choices made during these years. Images in pages, secure connections, scripting and cookies all came from this period, along with the habit of testing a site in more than one browser. The need for encryption on every page has only grown. Today a free SSL certificate comes with every Zebra Hosting plan, issued through Let's Encrypt, so that your visitors get the padlock that Netscape's SSL first made possible. And if your site was built long ago, check how it looks on modern phones, since design assumptions from the 1990s rarely hold now.
