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← Prefatory Pro Tips   |   Creating Files and Folders →

6. Navigation

Getting started: know thyself

You may also see your username to the left of the command prompt $. Let's try our first command. Type the following and press enter on your keyboard:

$ whoami

The whoami command should print out your username. Congrats, you've executed your first command! This is a basic pattern of use in the command line: type a command, press enter on your keyboard, and receive output.

Orienting Yourself in the Command Line: Folders

OK, we're going to try another command. But first, let's make sure we understand some things about how your computer's filesystem works.

Your computer's files are organized in what's known as a hierarchical filesystem. That means there's a top level or root folder on your system. That folder has other folders in it, and those folders have folders in them, and so on. You can draw these relationships in a tree:

An example of how a hierarchical filesystem looks

The root or highest-level folder on macOS is just called /. We won't need to go in there, though, since that's mostly just files for the operating system. On Windows, the root directory is usually called C:. (If you are curious why C: is the default name on Windows, you can read about it here.)

Note that we are using the word "directory" interchangeably with "folder"—they both refer to the same thing.

OK, let's try a command that tells us where we are in the filesystem:

$ pwd

You should get output like /Users/your-username. That means you're in the your-username directory in the Users folder inside the / or root directory. This directory is often called the "home" directory.

On Windows, your output would instead be C:/Users/your-username. The folder you're in is called the working directory, and pwd stands for "print working directory." "Print" as a word can be somewhat misleading. The command pwd won't actually print anything except on your screen. This command is easier to grasp when we interpret "print" as "display."

Now we know "where" we are. But what if we want to know what files and folders are in the your-username directory, a.k.a. the working directory? Try entering:

$ ls

You should see a number of folders, probably including Documents, Desktop, and so on. You may also see some files. These are the contents of the current working directory. ls will "list" the contents of the directory you are in.

Wonder what's in the Desktop folder? Let's try navigating to it with the following command:

$ cd Desktop

The cd command lets us "change directory." (Make sure the "D" in "Desktop" is capitalized.) If the command was successful, you won't see any output. This is normal—often, the command line will succeed silently.

So how do we know it worked? That's right, let's use our pwd command again. We should get:

$ pwd
/Users/your-username/Desktop

Now try ls again to see what's on your desktop. These three commands—pwd, ls, and cd—are the most commonly used in the terminal. Between them, you can orient yourself and move around.

One more command you might find useful is cd .. which will move you one directory up in the filesystem. That's a cd with two periods after it:

$ cd ..

Challenge

Before moving on, take a minute to navigate through our computer's file system using the command line. Use the three commands you've just learned—pwd, ls and cd—eight (8) times each. Go poking around your Photos folder, or see what's so special about that root / directory. When you're done, come back to your "home" folder with

$ cd ~

(That's a tilde ~, on the top left of your keyboard.)

Compare with the GUI

It's important to note that this is the same old information you can get by pointing and clicking displayed to you in a different way.

Go ahead and use pointing and clicking to navigate to your working directory—you can get there a few ways, but try starting from "My Computer" and clicking down from there. You'll notice that the folder names should match the ones that the command line spits out for you, since it's the same information! We're just using a different mode of navigation around your computer to see it.

Solution

  1. Type pwd to see where on your computer you are located.
  2. Type cd name-of-your-folder to enter a subfolder.
  3. Type ls to see the content of that folder.
  4. Type cd .. to leave that folder.
  5. Type pwd to make sure you are back to the folder where you wish to be.
  6. Type cd ~ to go back to your home folder.
  7. Type pwd to make sure you are in the folder where you wish to be.
  8. Type cd / to go back to your root folder.
  9. Type ls to see the content of folder you are currently in.
  10. Type pwd to make sure you are in the folder where you wish to be.
  11. Type cd name-of-your-folder to enter a subfolder.

Evaluation

What command do you run if you are trying to identify where in the filesystem you are currently located/working?

  • $ ls
  • $ pwd*
  • $ cd
  • $ whoami

When and why would you want to use the command line as opposed to your operating system's GUI?

Keywords

Do you remember the glossary terms from this section?

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