Have you ever wondered why the user-agent of your browser looks like:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US) AppleWebKit/525.13 (KHTML, like Gecko) Chrome/0.2.149.27 Safari/525.13
For Chrome you have reference to Mozilla, WebKit, KHTML, Gecko and Safari. Why that?
It pretends to be as good as all of them. If you want to know how this came and what was at the beginning and why Mozilla is called Mozilla, follow the link and read the history of browser user-agent strings.