The Command Line
For macOS and Linux
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If you would rather use a ready-made deck such as The Command Line, we ask you for a small sum in return. For €0.99 once you get 36 flashcards, sorted into 5 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 36
- Categories
- 5
- Price
- €0.99
Free, no account, no ads
What is in this deck
With this deck you learn the command line on macOS and Linux: moving and looking around, files, permissions and processes.
The command line is the window where you type instructions instead of clicking. On a Mac it is called Terminal, on Linux Terminal or shell; the commands in this deck work on both. On Windows they run in WSL, not in the classic prompt.
This deck asks about the situation, not the description: "How do you follow a log file while it grows?" The answer is the command. Where something is dangerous, the note warns, there is no recycle bin, rm -r is the sharpest command here, and after sudo no prompt protects you.
POSIX and the common GNU tools; where macOS differs, it says so.
The categories decide what comes up: start with “Files” alone and add the rest when you are ready.
What you learn
- 36 commands from cd to redirection
- find vs grep, one > vs two
- What the digits in chmod mean
The categories
5 categories sort the 36 cards. You can filter by category and take on what is due right now.
- Files
- Moving and looking
- Permissions and processes
- Searching
- Text and streams
What you get
Here are three of the 36 cards you get when you buy the deck.
Question
How do you show which directory you are in?
Answer
pwd
Note
Question
How do you list all files with details, hidden ones included?
Answer
ls -la
Note
Question
How do you change into a directory?
Answer
cd <ordner>
Note
Learning with Qardbox
You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.
What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.
Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.
What it costs, and what it doesn’t
Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.
Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.
It is a shortcut: 36 checked cards for €0.99, once, with Family Sharing. The work you would otherwise do is already done. The App Store shows the price in your currency.
Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every feature is included. The only thing that costs money is a ready-made deck like this one, €0.99 once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in The Command Line?
36 cards, sorted into 5 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
Is there a Qardbox for Android?
No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.
Other decks that go with this one
Get started
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