vi/vim

There are a few modes: insert, normal and command mode.

Normal mode (navigation)

Press the esc button from any other mode. This is the default mode.

Insert mode (typing & editing)

Press i from the normal mode. This mode allows us to directly insert and edit text — just like a normal text editor.

Command mode (executing commands)

Press : from the normal mode. This mode allows us to run several commands without leaving the editor. One feature I really appreciate is the ability to run shell commands — see below for more details.

Useful commands

1. Save (write) file

:w  

1. Quit

:q

1. Combine write + quit

:wq

1. Quit without saving

:q!

1. Execute shell commands

:!
:! ls

Note: The symbol % represents the current filename without any extensions

Examples

Eg. Compile and execute a C program file test.c (that is currently opened)

:! gcc test.c -o test && ./test
:! gcc %.c -o % && ./%

Eg. Execute a Python program file test.py (that is currently opened)

:! python3 test.py
:! python3 %.py

Eg. Change permissions and execute a .sh (shell) script test.sh

:! ls -l
:! chmod +x test.sh
:! ./%