What are woodwork planes used for?

A woodworking olane is a hand tool that shaves wood very smoothly. If you watch episodes of NCIS you will occasionally see the fearless leader in his basement, working on his pet project -- a boat. He uses a plane to carefully shave a wee bit of wood off one of the curved boat frames.

The extra fine planes are very long for two-handed control of the tool, compared to the short single-handed one he sometimes uses.