Many actors on The Office maintain blogs, some of which are written in character and others as themselves. NBC also publishes blogs written in the personas of characters on the show.
Initially, the entries were written by actor Rainn Wilson on the set. Eventually, the task of writing Dwight's entries was given to the Office writing staff.
After the introduction of Creed's "blog" in the episode The Job (really a Word document set up by Ryan, who unwilling to expose the innermost workings of Creed's brain to an unprepared human race), NBC created a blog called Creed Thoughts, written in the persona of the character Creed Bratton. The initial blog entry is a copy of the entry seen on Creed's monitor during that episode.
It is generally believed that the online Creed Thoughts entries were written by the Office writing staff.
In September 2008, NBC launched a new blog written in the persona of Meredith Palmer.
It is not known who wrote Meredith's blog.
Actor Jenna Fischer maintained a MySpace for herself. Some of the blog entries were written on the set while she was working background in a scene.