What is a terminal? The plain answer, and your first three commands

A terminal is the window where you give your computer commands in words. Learn terminal vs shell vs command line, how to open one, and try three safe commands.

What is a terminal?

A terminal is a window where you control your computer by writing commands instead of clicking. You type a short instruction, such as dir, press Enter, and the computer answers in text right underneath. Coding tools such as Git and AI coding agents work there, so every coder meets one sooner or later.

Here is the picture the DayOneCode course uses. Clicking icons is like pointing at pictures on a menu: easy, but you can only have what is shown. The terminal is like talking to the waiter. You say exactly what you want, in words, and you can ask for things no menu shows, such as "make a folder for every month of the year". The waiter does exactly what you say, no more and no less. That is the whole power of the terminal, and the one thing to be careful about.

Terminal, shell and command line: three jobs

People use these three words as if they meant the same thing. They are really three jobs that work together, and knowing which is which makes install guides and error messages far less confusing.

Microsoft puts it plainly: Windows has two command-line shells, the Command shell and PowerShell, and each is a program that lets you talk directly to the operating system. Windows Terminal is not a shell at all. Microsoft calls it a host application for shells such as Command Prompt, PowerShell and bash, so one Terminal window can hold several shells in tabs. Apple says the same about the Mac: each Terminal window runs its own shell, and Apple’s own example uses the default one, called zsh.

Stretch the waiter picture a little: the terminal is the table where you sit and speak, the shell is the waiter who understands your order and carries it out, and each command is one order. When a guide says "open a terminal and run this", it means all three at once.

Try it: your first three commands

Below is a practice terminal. It is a pretend Windows PowerShell on a pretend disk, so nothing you write here can touch your real computer. It starts in a folder called my-project, inside Documents. Try the commands in order and read each answer before the next one.

• pwd answers "where am I?" It prints the path of the folder you are standing in, which coders call the working directory.
• dir lists what is in that folder. Here that is one folder, images, and two files, hello.py and notes.txt.
• cd images walks into the images folder. cd .. walks back up one level, to the folder that holds it. The two dots always mean "the folder above".

Watch the prompt change after each cd. In the standard PowerShell prompt, the part between PS and > is your current path, so the terminal tells you where you are before you even ask. A path is a home address for a folder or file, and our guide to file paths shows how to read one.

How to open a terminal on Windows 11, Windows 10 and Mac

On Windows 11

1. Press the Windows key and X together. A menu opens.
2. Choose Terminal. On some computers the menu says Windows PowerShell instead, and that works too.
3. A window opens with a blinking line after PS C:\Users\yourname>. Windows Terminal starts with PowerShell in its first tab unless someone has changed that setting.

On Windows 10

1. Press the Windows key and X together.
2. Choose Windows PowerShell from the menu.
3. Check that the prompt starts with PS. If it does not, the next section explains what you have opened.

On a Mac

1. Press Command and Space to open Spotlight.
2. Type Terminal and press Return.
3. Another way: open Finder, go to Applications, then Utilities, and double-click Terminal.

On a Mac the prompt looks different. With the standard zsh shell it usually shows your name, the computer’s name, the folder you are in and a % sign, like sam@MacBook-Pro ~ % (the ~ means your home folder). A few command names change too, and Dialects: PowerShell, CMD, Mac covers them. You never need "Run as administrator" to learn: a normal window can reach your own files, which is all a beginner needs.

Am I in PowerShell or CMD?

Windows has two shells, and they speak slightly different languages, so an install guide written for one can fail in the other. The quickest check is the prompt, the text just before the blinking line.

PS C:\Users\you>   ← PowerShell (starts with PS)
C:\Users\you>      ← Command Prompt, CMD (no PS)

Anthropic's install guides for Claude Code, an AI coding tool, use exactly this test, and name two error messages that give the game away. If you see The token '&&' is not a valid statement separator, you are in PowerShell, not CMD. If you see 'irm' is not recognized as an internal or external command, you are in CMD, not PowerShell.

DayOneCode teaches PowerShell. It is the shell Windows Terminal opens first, and Microsoft notes that it can run both its own commands (called cmdlets) and the classic Windows commands, while CMD cannot run cmdlets. PowerShell vs CMD goes into the differences, and PowerShell for beginners is the next step.

Is the terminal safe?

Yes, if you read before you press Enter. The terminal is not dangerous in itself, but it does exactly what you say, straight away, and it usually does not ask "Are you sure?" Some beginner pages claim you cannot damage anything by writing in a terminal. That is not true, and here is the one fact to remember.

Deleting with a command skips the Recycle Bin. Microsoft’s own page for the del command warns that a file deleted with it cannot be retrieved. PowerShell’s rm (its full name is Remove-Item) works the same way: the file is gone, not moved to the bin. So learn these habits from day one:

• Look before you delete. Run dir first to see exactly what is there. Microsoft suggests the same before deleting with wildcards.
• Add -WhatIf to a PowerShell delete. It reports what the command would do, and does nothing.
• Never paste a command you do not understand, whether it comes from a stranger, a video comment or a pop-up on a website.
• Skip "Run as administrator". Learning never needs it, and the less a window is allowed to touch, the less a slip can break.
• Practise on a pretend disk first, where a slip costs nothing.

dir
rm notes.txt -WhatIf

Delete carefully and Commands have parts drill both habits in the course, so they are automatic before you ever delete a real file.

Why coders and AI coding agents use it

If clicking works, why bother? Because the terminal does three things that clicking cannot.

• It repeats work. One line can do what would take fifty clicks, and a list of commands saved as a script can do it again tomorrow. Microsoft says scripts get jobs done more efficiently than the user interface.
• It reaches every tool. Git, the tool coders use to save versions of their work, says in its own book that the command line is the only place you can run all Git commands.
• It is plain text. A command can be written down, shared, checked and repeated exactly, which is hard to do with a trail of clicks.

Code editors know this. Visual Studio Code has a terminal built in: choose Terminal, then New Terminal, and it opens in your project folder using the usual shell on your computer.

AI coding agents work in the terminal too. Claude Code, for example, is described by its makers as a tool that reads your code, edits files and runs commands, and it can run right inside a terminal. On Windows without Git for Windows, it runs those commands in PowerShell. Think of an agent as a fast helper who is new to your house. It can suggest a command in a second, but someone has to check that it is a good idea before it runs, and that someone is you. So the most useful skill you can bring is reading a command and knowing what it will do. You are the boss.

Real agents need an account: most ways to use Claude Code need a Claude subscription or an Anthropic Console account, and setting that up is a job for a grown-up. You can practise being the boss without one. Levels 8 to 10 of Learn to code use a scripted, pretend agent, and What is an AI coding agent? explains the rest.

Where to go next

Start with Meet the terminal, lesson 5 of the free DayOneCode course. It needs no account and no install, and it builds on the first four lessons about computers, files, folders and paths. When the commands feel familiar, race them in Command Racer, drill them on the practice page, and keep the PowerShell cheat sheet open beside your real terminal.

Try it on DayOneCode

• Meet the terminal

  Lesson 5 of the free course: your first dir and cd, in a practice terminal that cannot touch your real files.

• Where am I? (pwd)

  Level 2 starts here: read the prompt, ask pwd, and never get lost in your folders again.

• Delete carefully

  Practise rm on a pretend disk, and learn why deleting with a command skips the Recycle Bin.

• PowerShell cheat sheet

  Every command the course teaches, on one page, with what it does and a safe example.

More from the blog

• Which Windows shell should a beginner learn: PowerShell or CMD?

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• What is a file path? Every file’s home address, explained

  A file path is the address of a file on your computer. See Windows and Mac paths side by side, absolute vs relative paths, how to copy a path, and try it safely.

• What is an AI coding agent? What it does, and how to stay the boss

  An AI coding agent reads your project, edits files and runs commands. See how it differs from a chatbot, how to stay safe, and who is old enough to use one.