MOUNTAIN VIEW, Calif. – If Google’s new Chrome Web browser succeeds, going online will be an all-Google experience.

“The Web has evolved pretty dramatically, but the underlying browser architecture is still very similar to the original Netscape browser,” Sundar Pichai, Google’s vice president of product management, said at a press conference Tuesday at the company’s Silicon Valley headquarters.

Google (GOOG) says Chrome was designed to be “streamlined and simple.” The browser is available for free download in 100 countries starting Tuesday. Initially it will only work on Windows computers, though versions for Mac and Linux operating systems are being developed.

According to Pichai, Google’s intent is to “drive the whole Web platform forward” and thus drive more people to the search giant.

At first glance, Chrome doesn’t look all that different from Mozilla’s Firefox, a competing browser. But unlike Firefox, Chrome combined the address and search boxes to let people search for information and Web sites by entering keywords into the same bar.

“What we did is we smashed the two boxes together,” said Ben Goodger, a software engineer at Google and former Mozilla employee. “We call it the ‘Omni Box.’ ”

The Omni Box lets users search for information and go to Web sites directly by typing into the same bar. Other Chrome features include movable “tabs” and an “incognito” window that lets people browse without saving their search history – a feature found on other browsers and which bloggers have nicknamed “porn mode.”

Google also said its new Web browser will be faster and more reliable than existing browsers. On Chrome, each tab operates separately so, if one crashes, it won’t affect the main browser window.

Chrome is being released as an open-source project, meaning developers will have access to build new features for the browser. Google said its engineers worked on the new browser for about two years.

“It is a huge investment for us,” said Pichai, who added that many Googlers are already using Chrome – including the company’s co-founder Larry Page, who made an appearance at the press conference.

But Chrome is entering a competitive market that Microsoft (MSFT) has dominated for years. The company’s Internet Explorer, which comes pre-installed on computers, accounts for 72% of the browser market. Runner-up Firefox has a 20% share.

“The browser landscape is highly competitive,” Dean Hachamovitz, general manager of Microsoft’s Internet Explorer, told Fortune. “But people will choose Internet Explorer 8 for the way it puts the services they want right at their fingertips, respects their personal choices about how they want to browse and, more than any other browsing technology, puts them in control of their personal data online.”

So is there room for another browser?

Yes, says Citi Investment Research analyst Mark Mahaney.

“There is market demand for a browser that is speedier, simpler, safer, and stabler than IE,” Mahaney wrote in a report Tuesday morning. “What is unknown is whether Chrome is that browser.”