Twitter has bought microblogging firm Posterous, which will remain up and running without disruption, Twitter said in a blog post on Monday.

"We'll give users ample notice if we make any changes to the service," it added. For users who would like to back up their content or move to another service, Twitter will provide instructions for doing so in the coming weeks.

"We're always looking for talented people who have the passion and personality to join Twitter," the company said, indicating that it acquired Posterous with an eye on its staff.

The financial terms of the deal were not disclosed.

Posterous in San Francisco was started in July, 2008, and developed and launched Posterous Spaces with a focus on allowing both private sharing within small groups, and broadcasting to a wider audience.

"The opportunities in front of Twitter are exciting, and we couldn't be happier about bringing our team's expertise to a product that reaches hundreds of millions of users around the globe," Sachin Agarwal, founder and CEO of Posterous said in a blog post.

Agarwal said in a post on Posterous Spaces that he will be a product manager at Twitter, but did not specify his area of work.