GOOGLE is taking yet another stab at social networking, as it tries to go up against Facebook in this wildly popular and lucrative segment of the internet.

In a dramatic about-face, Ask.com is abandoning its effort to outshine internet search leader Google and will instead focus on a narrower lifestyle market of married women.

In a major expansion, Yahoo says its online search engine index now spans more than 20 billion web documents and images, nearly double the material scanned by rival Google.

Google is using its popular internet search technology to find information and images broadcast on US television, continuing a recent effort to extend its reach beyond the web.