A file is one of the most useful tools you can have in a workshop, but they're rarely fully understood and appreciated in our modern mechanized age.
Files have been around for over three thousand years, and before machine tools became available they were one of the primary means of making precision objects!
In this video I show the basic types of files, the differences between them, and how to use them.
Here is a nice set of files to get started with: http://amzn.to/1xAbPvI
Make sure to get a file card for cleaning your files: http://amzn.to/1sXoVnv
I also highly recommend a sturdy vise when using files: http://amzn.to/1wiFcEp
-Aaron