Firms that serve ads alongside casual games will face new competition from a familiar name -- Google. The search giant has announced plans to bring its AdSense network to the casual gaming market.

The ads, which can be text, graphic or video, will run just before the game, in between levels and after the game is over. The ads cannot be skipped.

"Brand advertisers come to us looking for a cross-platform solution that lets them hit audiences that are on the scale of millions but allows them to do very precise targeting," Christian Oestlien, a Google product manager, told The New York Times.

Casual games are played by tens of millions of users, but Google said it is planning to focus on delivering to the coveted the 18- to 35-year-old demographic.