RegExr
This is one of my personal favourite. Regexr is a simple web app for learning, building, and testing Regex. It also has a cheatsheet for Regex.
Explain Shell
A web app for explaining each part of a shell command.
Arch Wiki
One of the best documentation about linux. Used mainly for arch linux but some of it’s content also applies to other linux distribution as well.
Openvim
Resource for learning vim interactively on the web.
20 Amusing Linux Command
In the spirit of trying many linux commands, this is 20 other unique and fun linux command to try.
Linux Directories Explained in 100 Seconds
Linux has different file hierarchy than windows, this video explains the basic of linux file structure in 100 seconds.
Vi vs Vim
This statckexchange post explain vi vs vim.
Neovim
Turns out there’s also neovim! Neovim is a more modern text editor based on vim.
Git Cheatsheet
A simple cheat sheet for git. If you go to the basedomain, there’s also cheatsheet for other languanges.
Resource for awk, sed, and grep
Stackexchange post for a few information regarding resource to learn grep, awk, and sed.