Comment by adventureloop

Another really useful command is the open

    $ open filename.png
    $ open .
    $ open -e filename.txt
    $ open -a Pixen filename.png

The first command will open the file with the default application.

Open . will open the current directory in finder, which I find very helpful.

The -e flag will open the file in textedit.

The -a will open the file in the given application name.