Google Inc., owner of the most popular Internet search engine, said rival Yahoo! Inc. will support its OpenSocial software, allowing developers to put their programs on a broader range of social-networking sites.

Yahoo, Google, and News Corp.’s MySpace are forming the non-profit OpenSocial Foundation to promote the technology. OpenSocial, introduced in October, may help developers save time and money by letting them create a single application that works on multiple sites.

Teaming with Yahoo gives the alliance the backing of the most visited American Web site. Google and sites such as MySpace, the most popular social-networking page, have sought more programs to appeal to users as they compete for advertising revenue in a market that may grow 69% in the next three years.

“Google has been doing a great job of shepherding the community to some degree,” the vice president of Yahoo, Wade Chambers, said on a conference call. “It’s a community-based effort and I think that this just really takes them to the next step.”