The first drawings are called "roughs" or "rough animation" because they are often done in a very loose fashion. If the animation is successfully pencil tested and approved by the director, clean versions of the drawings have to be done. In larger studios this task is given to the animator's assistant, or, in a more specialised setting, to a clean-up-artist. The artist doing the clean-ups has to have better drawing skills than the animator, and he has to painstakingly follow the model sheets of the characters.
Clean-ups generally are done on a new sheet of paper. They can be done on the same sheet as the rough animation if this was done with a "non-copy blue" pencil. This certain tone of blue will be invisible for photocopying machines or grayscale scanners, where the finished animation will be copied on cels or transferred into a computer for further processing.
A naval tradition of evading leaders for a specific period of time.