COMMANDS

1. stands for “stream editor”. It accepts standard input and modifies it based on an expression, before displaying it as output data.
2. short for “unique”, takes a filename or standard input and prints out every line, removing any exact duplicates.
5. takes in a directory name as an argument, and then creates a new directory in the current working directory. Here we used mkdir to create a new directory named media/.
7. makes the variable to be available to all child sessions initiated from the session you are in. This is a way to make the variable persist across programs.
8. is an environment variable that stores a list of directories separated by a colon. Each directory contains scripts for the command line to execute. PATH lists which directories contain scripts.

1. ctivates the changes in ~/.bash_profile for the current session. Instead of closing the terminal and needing to start a new session, source makes the changes available right away in the session we are in.
3. lists all files and directories in the working directory
4. takes a filename or standard input and orders each line alphabetically, printing it to standard output.
6. reates a new file inside the working directory. It takes in a file name as an argument, and then creates a new empty file in the current working directory. Here we used touch to create a new file named
9. command allows you to create keyboard shortcuts, or aliases, for commonly used commands.