The country decided to banned access to Slide, a presentation application. According to the company’s blog, the Slide was "harboring pictures and articles that are considered to be insulting to Ataturk."
The company adds that they have the government of Turkey in an effort to resolve this situation:
“In the meantime, we’re trying our best to enable Turkish citizens to access our website and applications again. Slide joins several other popular web services such as YouTube, Facebook and MySpace that have been banned in various countries (including Turkey, Pakistan, China and the UAE) for user-generated content.”