Command Line Interface (CLI): Before icons and windows tools over computer screens, commands are typed to run most computers. On UNIX systems, from which Red Hat Linux was derived, the program used to interpret and manage commands was referred to as the shell. The shell interface provides a way to run programs, work with the file system, compile computer code, and manage the computer. If you type something wrong on a command line, the shell ensures that you have to delete the entire line and start over. As you edit a command line, you can type regular characters. The character appears at the location of your cursor. You can use right (→) and left (←) arrow keys to move the cursor from one end to the other on the command line. There are many keystrokes you can use to edit your command lines.

Keystrokes for Editing Text in Command Lines:

Keystroke → Meaning

Alt + t → Switch positions of current and previous words 

Alt + U → Change the current word to upper case

Alt + l → Change the current word to lower case

Alt + c → Change the current word to the initial capital

Ctrl + d → Delete the current character

Ctrl + t → Switch positions of current and previous characters

Ctrl + v → Insert a special character

Keystrokes for Editing Text in Command Lines:

Keystroke → Meaning

Alt + d → Cut the word followed by the cursor

Alt + y → Paste the earlier cut text

Ctrl + c → Delete the entire line

Ctrl + k → Cut text to the end of line

Ctrl + u → Cut text to the beginning of the line

Ctrl + w → Cut the word

Ctrl + y → Paste latest cut text