Jack of all trades

"Jack of all trades, master of none" is a figure of speech used in reference to a person who has dabbled in many skills, rather than gaining expertise by focusing on one.

The original version "a jack of all trades" is often a compliment for a person who is good at fixing and has a very good broad knowledge. They may be a master of integration, as such an individual who knows enough from many learned trades and skills to be able to bring the disciplines together in a practical manner. This person is a generalist rather than a specialist.

- Wikipedia on Jack of all trades