Twitter has acquired Posterous, a startup that builds products that makes sharing across the web and mobile devices simple.

Posterous engineers, product managers and others will join Twitter's teams.

San Francisco-based Posterous started in 2009 as a publishing platform similar to Tumblr and WordPress.com. It has been focused on simple posting, deep email integration and provided users the ability to distribute Posterous content to a number of other locations (e.g. WordPress, Twitter, Facebook, Linkedin and more) with ease. The company had also developed 'Spaces', a place where users could share privately or publicly with their friends, family or groups. Each Space comes with its own custom web address and the look and feel can be customized.

Posterous Spaces will remain up and running without disruption. For users who would like to back up their content or move to another service, Twitter plans to share instructions for doing so in the coming weeks.