It works with most Web browsers and operating systems. The new Yahoo chat client differs from most other Web-based clients in that it is based on Adobe Systems’ Flash.

However, the announcement is important due to the sheer number of people who use Yahoo Messenger: 88.5 million, according to Yahoo, a number that grew substantially last year when Yahoo and Microsoft announced interoperability between Messenger and Windows Live Messenger, Microsoft’s IM product. Yahoo is far from the first Internet player to offer a Web-based instant messaging service - AOL, Google, Meebo and eBuddy are among the competitors. The new application is “the first brand-new Messenger in over six years,” noted Jeff Bonforte, vice president of product development for Yahoo Messenger, in his blog. That means Yahoo Messenger users can log in to chat on any computer or other device with Web access, including PCs at companies that forbid software downloads.

Still in the beta phase, the new “Yahoo Messenger for the Web” is browser-based.

Yahoo has introduced a new version of its popular Yahoo Messenger instant messaging service that eliminates the need to download and install software.

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