Terminal essentials

If you’re new to working with Terminal, here are some key things you should know.

Note: I’m wrapping up production on a new series of courses on developer tooling. The first course on Terminal should be ready in the next week or two, but you can pre-order it today. This is an excerpt from the guide.

Running commands

Throughout this guide, we’ll be looking at Terminal commands that you can use to work with the command line.

To run any of them, press the enter or return key.

Most Terminal commands accept options, typically prefixed with a dash (-) and grouped together, and arguments. Both are typed after the command itself.

<command> <-options> <argument1> <argument2>

Quitting things

Sometimes, you’ll run an ongoing task, or one that takes a long time to complete, and want to quit it.

To quit an active or ongoing task, use the Control + C keys.

For example, the ping command makes repeated calls to a website. We can ping google.com, and we’ll get a response printed in Terminal every second or so. To stop it, we press Control + C.

# Ping Google
ping google.com

# Something like this starts printing
PING google.com (142.251.40.238): 56 data bytes
64 bytes from 142.251.40.238: icmp_seq=0 ttl=117 time=28.667 ms
64 bytes from 142.251.40.238: icmp_seq=1 ttl=117 time=26.424 ms
64 bytes from 142.251.40.238: icmp_seq=2 ttl=117 time=27.626 ms

# Stop the process by pressing Command + C

Some commands open up a subwindow in Terminal. You can quit the subwindow and return to the main Terminal view by pressing q.

For example, the top command shows all active processes. Pressing q exits the subwindow.

# Show all active processes
top

# Press q to quit

Sometimes, you need to prefix q with a colon (:q).

For example, the vim command opens a text editor that’s notoriously confusing to Quit. Running :q quits Vim.

# Start vim
vim

# Run :q to quit vim

Getting help

Through this guide, we’ll be learning about many built-in Terminal commands.

To avoid overloading you with too much information, this guide is focused on the Terminal commands and options that you’re likely to use most often.

Terminal includes a built-in manual that you can use to explore the full set of options available for any of the built-in commands. This is also useful if you forget how a command works.

Run man followed by the command to learn more about how it works.

For example, this would open up the manual for the echo command.

# Open up the manual for the echo command
man echo

The man command opens up a subwindow. You press q to quit and return to the main Terminal view.

Start of line/End of line

Terminal is keyboard based. You can’t use a mouse to skip to the start or end of a line.

Fortunately, there are keyboard shortcuts for that. Press Control + A to jump to the start of line, and Control + E to jump to the end.

Command History

Pressing the up arrow cycles through the history of commands that you’ve run in Terminal. If you press enter or return, Terminal will run the current command in your history again.

This is useful if you want to run a command over-and-over again.

For example, you can press the up arrow, then return, to rerun the last command you ran.