progit/progit — pull request #555 by isomorphisms (2013-12-07 06:33:10+00:00)
Title: Update 01-chapter1.markdown

Is a simple file distinct from some other kind of file?

Also, I don't understand this sentence:
> The working directory is a single checkout ....

What is "a checkout"? I understand checkout is a verb and git co is a command I can run. Not sure what "a checkout" is.