A new internet browser that requires a Facebook log-in has been unveiled, aimed squarely at social networking users called RockMelt, it has been set up by Marc Andreessen, the founder of Netscape. Based on Google's Chromium software, Rockmelt is designed to let users share everything they do with the friends on Facebook and Twitter.

Down the side of each web page visited is a selection of each user's most-used Facebook Friends and Twitter contacts, reports the Daily Mail. A statement on the firm's blog read: "With RockMelt, we've re-thought the user experience, because a browser can and should be about more than simply navigating Web pages. Today, the browser connects you to your world. Why not build your world right into your browser. The browser makes it particularly easy to share links with friends by dragging pictures, URLs or videos onto one of the small photos, known as 'edges' that line the browser's window.

Because you have to sign in before using Rockmelt, all of your favorite sites, blogs and friends are listed when you log in. The browser alerts you when a new story, video, or post appears on the sites you visit the most, without you having to leave the webpage you are currently on. However, the fact that a user's entire web search history, friends and favorite sites are known by RockMelt, will alarm those wary of handing over personal information to tech firms.

The firm claims that this browsing information will not be sold to advertisers.

We are not going to run an ad network. We actually don't know where you go," co-founder Tim Howes told website TechCrunch. "That information does not leave your browser. The way you search on the internet is also different with RockMelt. Instead of a whole page of search results from Google, only the first 10 results come up, displaying the web page of each result before you click on it.