LS

The ls tool is used to list file and directories in the specified directory or your current directory if one isn't specified. For example running: ls / would show all the files and directories on the root of the hard drive.

Some important flags to ls command to know are:

-a

shows hidden and 'dot' files

-h

adds a header row to each column

-l

displays extended file metadata as a table

These flags can also be chained together like this: ls -lah. For any more information on the ls tool please refer to the Man page for ls.