Wanted to share a few resources I discovered while studying. The first is some files and directories provided by Linux Pocket Guide. When you are first playing around with Linux and performing text manipulation and file comparisons you need directories and files to work with. The Linux Pocket Guide provides these resources. I recommend you buy the book, but if you don’t the files are publicly hosted. The two commands below will download and extract the files.
tar -xf LPG-stuff.tar.gz
The other cool thing I discovered was a linux password auditing command. This command will display registered users that have access to the system.
grep -v nologin$ /etc/passwd