i just downloaded msysgit from http://msysgit.github.com/ and am trying to learn how to use it. i also downloaded a copy of the pro git manual from their wiki.
In chapter
The "Git Bash" terminal will put the root of each drive in /<drive-letter>, so drive C:\ will be at /c/, drive E:\ will be at /e/, etc. Try cd /c/myapp/abc.