A Silicon Valley start-up is entering one of the most hotly contested software markets -- Web browsers -- with a strategy to integrate social networking and other features that have changed the way people use the Internet.

Closely held company RockMelt is backed by investors that include Marc Andreessen -- who helped develop and popularize the first widely used browser -- and William Campbell, a veteran technology executive who is chairman of Intuit and a board member of Apple Inc.

RockMelt, which is to release a test version of its software on Monday, is entering a market dominated by Microsoft's Internet Explorer, Mozilla's Firefox, Google's Chrome browser and Apple's Safari. The start-up hopes to differentiate its product with some fundamental technical differences.

One is that RockMelt isn't only software. It comes with an Internet service that the company will operate and use to funnel updated information to users.

They must log into the software, using their credentials from Facebook. The design allows information about friends from the popular social network to appear without having to keep returning to Facebook.

A selection of a user's Facebook friends remains on one edge of the browser, making it easy to send instant messages to them or share videos or other items by dragging it to that portion of the screen, said Eric Vishria, RockMelt's co-founder and chief executive. Another key feature, he said, is that updates from news sites are pushed constantly to the browser, so users don't have to keep visiting those sites for the latest information.

"The way people use the Web has changed dramatically over the years, but browsers haven't changed much," Mr. Vishria said. RockMelt "brings the browser into this decade," he said.

Read more at the Wall Street Journal.