Vim is a highly configurable text editor built to enable efficient text editing. It's included in many Unix-like operating systems, including Linux and macOS, and is available for other platforms as well. Understanding Vim can be beneficial for tasks such as editing configuration files, programming, or making quick changes in a terminal environment, enhancing overall productivity on these systems.

Moreover, for certain commands like less and man the search and navigation commands resemble those of Vim.

There are two modes in Vim, when you open a document or you press Esc button, you're in command mode and you can run the following command:

i insert mode
a append, move cursor forward and insert
x,X delete one char
o,O open new line
r replace one char
u undo
ctrl+R redo
d delete (dw, dd,D or d$ deteles from cursor to the end of the line)
G go to line (10G, 1G, G)
y yank/copy (yy, yw)
p,P paste
/X search for X (n,N find next/prev)
$ end of the line
^,0 start of the line
. repeat

You can set settings for current session using :set command. For example for displaying line number you can use :set number. If you want to get a list of available command, in command mode press ctrl+d to show you the list of available commands.

If you want to set settings permanently you need to add them to ~/.vimrc file:

:set number
:syntax on
:set tabstop=2