The Unix Command Line
In the days before graphical user interfaces (GUI), computers were operated by entering commands to a prompt in the terminal. It’s a text interface for keyboard entry (no mouse). You can perform almost all the same tasks as that can be done on GUI.
Today, it is still important to know how to use the unix command line if you're working with cloud computing.
Many of the commands are one word in lowercase such as the following:
cat: shows the contents of a file, all at once
more: shows the contents of a file, screen by screen
less: also shows the contents of a file, screen by screen
head: used to show so many lines from the top of a file
tail: used to show so many lines from the bottom of a file
script: used to record commands and their output
cat foo.txt | sortwith
-nnumeric sort or
- comm to compare using set operations
- uniq to find unique lines
- cat lets you concatenate multiple files