Google will power Internet search across AOL properties and AOL video will appear on YouTube under an agreement reached on Thursday between the Web companies.
AOL, whose websites include online map service Mapquest and technology blog Engadget, and Google said the five-year deal includes a revenue-sharing arrangement but they did not release any financial details of the agreement.
Microsoft was also reportedly seeking a search agreement with AOL, but the once high-flying Internet portal eventually decided to continue its long-term partnership with Google.
"Today is another important step in the turnaround of AOL," AOL chairman and chief executive Tim Armstrong said in a statement.
"AOL users will be getting a better search and search ads experience from the best search company in the world - Google," said Armstrong, a former top executive at the Internet search giant.
"After nearly a decade-long partnership in search, we're looking forward to expanding our global relationship to mobile search and YouTube," he said. "All aspects of our partnership will be improved by this deal."
Google chairman and chief executive Eric Schmidt said the agreement with AOL "combines Google's expertise in search and advertising with AOL's strength in online content.
"It's particularly exciting to see our relationship expand into video and mobile," Schmidt said. "These areas are now at the heart of users' online experiences and at the core of both of our businesses."
AOL merged with Time Warner in 2001 at the height of the dot-com boom in what is considered one of the most disastrous mergers ever.
AOL was spun off by Time Warner in December into an independent company.
Armstrong has embarked on an aggressive round of cost-cutting since taking the reins at AOL last year and has said he plans to refocus the company on "content, ads and communications."Reuse content