Despite having dabbled in *nix off and on for 35 years, it is only T that IL about cheat.

It's a wonderful wee command, which saves you from having to switch focus to a browser and rummage through Stack Exchange, by the simple expedient of giving you a few examples of a command you're about to use, thus obviating the need to hold vast amounts of syntax in your head.

An example:

 $ cheat ls
# To display everything in <dir>, excluding hidden files:
ls <dir>

# To display everything in <dir>, including hidden files:
ls -a <dir>

# To display all files, along with the size (with unit suffixes) and timestamp
ls -lh <dir>

# To display files, sorted by size:
ls -S <dir>

# To display directories only:
ls -d */ <dir>

# To display directories only, include hidden:
ls -d .*/ */ <dir>

To install this wonderful command, do this:

$ sudo snap install cheat

Of course, if you're not using snap, you'll first need to do this:

$ sudo apt update

$ sudo apt install snapd

I should say that I pinched these instructions from Snapcraft