Coding glossary

AI lets a computer do things like recognise a photo or write text. Many kinds of AI learn from examples. What AI makes can be wrong.

AI suggests a game rule. You try the rule and check that the game is still fun and possible to play.

A clear plan of steps for doing something or working something out. A computer can follow steps like these.

When following a recipe, you measure the ingredients first. Then you mix them. The order matters.

A technical name for a kind of processor, the part that carries out computer instructions. Many computers with Intel or AMD processors use this kind. It is also called x64.

A download might say ‘Linux AMD64’. That tells you which system and kind of computer the program was built for.

Changing pictures quickly, one after another, so that something looks as if it is moving.

Draw a character in the corners of a notebook, with its legs a little different each time. Flick through: it looks like it is walking!

Rules that let one program ask another program for something. They say which requests are possible and how to make them.

A weather app uses an API to ask, ‘How warm is it in Utrecht?’ The weather service sends back an answer.

A set of instructions that makes a computer carry out a task. An app is a program for a particular purpose.

A game, a calculator and a drawing program are all apps.

An extra copy of your work kept somewhere else. It can help you get your work back if the original is lost or damaged.

You keep an extra copy of your game on a USB stick. If your computer breaks, you still have that copy.

Instructions you put together as blocks. Their shapes and words help you see what each block does. Together, they form a program.

You put a movement block inside a repeat block. The computer then makes that movement more than once.

A value with just two possibilities: true or false. A program uses it to remember whether something is the case.

Is the door open? The answer is true when the door is open, and false when it is shut.

A program you use to open websites. It shows the text, pictures and other parts of a website.

You are reading this glossary in a browser, such as Edge, Firefox, Chrome or Safari.

A mistake in a program that makes something happen differently from what you intended. Even experienced programmers make these mistakes.

You collect a coin, but your score goes down. There might be a minus where you wanted a plus.

The instructions you write for a computer. Together, they tell a program what to do. The original text is also called source code.

You write instructions to draw a line and then turn a corner.

A note for people reading the code. The computer skips the note when carrying out the instructions.

You add a note beside some code: ‘This gives the player an extra life.’ It reminds you what that part does.

Turning code into a form a computer can run. The tool that does this is called a compiler.

Pliro can turn your project into a Windows program. You can then start that program on its own.

A check that helps a program choose what to do. It carries out an instruction if something is true.

If the score is 10 or more, the message ‘You win!’ appears.

Numbers that tell you where something is. In a drawing, they might tell you how far right and how far down to go.

Think of a grid map. From the start, count 3 squares right and 2 down. That is where the treasure is.

The kind of information you are working with, such as a number or text. The kind tells you what you can do with it.

You can do sums with the number 4. You can make a message with the text ‘hello’.

A collection of information that a program stores in an organised way and can search. The program can also add or change information.

A library uses a database to keep track of its books and whether they are on loan.

Finding out why a program is not doing what you want, and trying to fix the problem. Look carefully and change one thing at a time.

Your score goes down. You check the coin instruction, change the minus to a plus and try again.

Getting a copy of something from another computer onto your device. This often happens through the internet.

You download an example game from a website. The file is then on your computer.

An editor is a program where you write code. An IDE brings several tools together. For example, you can write, save and try out code in one place.

The Pliro workspace shows your instructions and their result side by side.

A message that tells you something could not be done. It often gives you a clue about where to look.

The computer says it does not know ‘scor’. You check whether you meant the name ‘score’.

Something that happens and that a program can respond to. It could be a click, a key press or a timer going off.

You press the space bar. That event makes your character jump.

Making a version of your work to use somewhere else or share. The choices depend on the program you are using.

In a drawing program, you export your drawing as a picture to send to someone.

A named piece of information saved on your computer. A photo, a song and some code can each be a file.

You save your code with the name mygame.pliro. Later, you open that file again.

A place to keep files together. It is like a real folder where you sort papers.

In a folder called ‘My game’, you keep your game’s code, pictures and sounds.

A group of instructions with its own name. You can use that name to run the group in different parts of your program.

You call a group of drawing instructions ‘drawFlower’. Each time you use it, the computer draws a flower.

Pins that let a computer receive or send signals. A Raspberry Pi has these pins. A program can use them to work with a button or a light.

You press a connected button. Your program notices and turns a light on. Get help when connecting the parts.

The parts of a computer you can touch. Think of the screen, keyboard and parts inside the case.

The keyboard is hardware. The game you control with it is software: a program.

Information that goes into a program. It might be something you type, a click or a signal from a button.

You type your name into a quiz. That name is input for the program.

A step for the computer to carry out. Lots of small instructions can work together to make something bigger.

Draw a line. Turn right. Draw another line.

Lots of computer networks connected together. They let devices around the world exchange information.

You open a website stored on a computer in another country. The information reaches you through the internet.

A program that reads and carries out the instructions in your code. Think of someone reading a recipe and following its steps.

You start a program. The interpreter carries out an instruction to draw something and moves on to the next instruction.

A way to write information as text using agreed rules. Programs can use it to save or exchange information.

A player’s name and score can look like this: {"name":"Pli","score":10}.

A collection of ready-made pieces of code that a program can use. You do not have to invent every instruction yourself.

You use an existing instruction to draw a circle. You do not have to work out every dot around its edge.

A licence is permission to use a program under certain rules. A licence key is a code the program can use to check that permission.

You can request a Pliro Learner key for free. A grown-up can help with the request and reading the rules.

An operating system: the main software that makes a computer work. It manages things like the screen, files and other programs. Windows is another operating system.

Two computers can look the same, while one uses Windows and the other uses Linux.

A row of items that belong together. You can add an item, remove one or look at each item in turn.

A shopping list contains bread, apples and milk. A game can keep a list of player names.

A way to repeat the same instructions. You can choose how many times, or keep going while a condition is true.

To draw a square, repeat this four times: draw a line and turn a quarter turn.

A program built to run directly on a particular kind of computer. It needs to match that computer and the system it uses.

You build a Windows game with Pliro. You can then start it on a suitable Windows computer without opening the Pliro workspace.

Devices connected so they can exchange information. They can connect using cables or without wires.

At home, a computer and a printer can be on the same network. You can send your drawing to the printer.

Online means connected to the internet. Offline means not using an internet connection. What still works depends on the program.

A game stored entirely on your computer may work without the internet. Getting a new website needs a connection.

The main software that makes a computer work. It helps other programs use things like the screen, keyboard and files.

Windows and Linux are operating systems. They help you start programs and find your files.

The result a program sends out. It can be text, a drawing, a sound or a signal.

The quiz shows ‘Well done, Sam!’ That message is output.

A place in a function where you pass in information. This lets the same group of instructions work with different numbers or text.

A function draws a circle. You pass in the size: 10 for a small circle, 50 for a larger one.

A choice about what a program is allowed to use. This might be a file, the camera or an internet connection.

A drawing program asks to open a photo. You read the request and choose whether you want to allow it.

A tiny dot in a picture. A screen image is made of lots of these dots. Each one has a colour.

If you zoom in a long way on a small picture, you can often see the separate coloured squares.

A series of steps in which something happens or changes. You can look at what happens at each step.

A quiz asks a question, waits for your answer and then shows whether it is right.

A part inside a computer that carries out instructions and does calculations. It works together with the other parts.

Your game adds up the points. The processor carries out the calculation.

A way to write instructions for a computer. Each programming language has its own words and rules. Pliro is a programming language for children.

In Pliro, you can write instructions in English or Dutch. You can also work with blocks.

Telling a computer what to do, step by step. You choose the instructions and try them out to see if they work.

When you press the arrow key, your program makes the character walk to the right.

Everything that belongs to one thing you are making. For a program, that might include code, pictures, sounds and settings.

The rocket, sounds and rules for your space game all belong to the same project.

A small computer you can use for things like games or an invention with lights.

You can connect a light and a button together. You do not need a Raspberry Pi to start using Pliro.

Starting your program so the computer carries out its instructions. You can then check whether it does what you intended.

You press Start. The turtle follows your instructions and draws a shape.

Keeping your work so you can open it again later. Remember to save the changes you make afterwards too.

You add a new room to your game and save your work. Tomorrow, you can carry on from there.

The order tells you which step comes first and which comes next. In coding, changing the order can change the result.

Put on your socks first, then your shoes. Doing it the other way round is tricky!

The programs on a computer, tablet or phone. They tell the device what to do.

A game, a web browser and a drawing program are software.

A picture that a program can move or change on its own. Games use sprites for things like characters and coins.

Your character walks left while the background stays in place.

The rules for how you write code. The computer needs these rules to read your instructions.

If a word is in the wrong place, the computer may ask you to write the instruction differently.

Trying out a program to check that it does what you expect. Try unusual things too, so you can find mistakes.

You test a quiz with a right answer, a wrong answer and an empty answer box.

Sending a copy of something from your device to another computer. This often happens through the internet.

You send a drawing from your computer to your class website. That is uploading.

The parts you use to control a program and see its results. Think of buttons, menus and boxes you can type in.

On a calculator, the number buttons and the box showing the answer are part of the user interface.

A piece of information a program works with. It can be a number, some text or a yes-or-no answer.

Score holds the number 5. The name is score; the value is 5.

A named place where a program remembers something. What it holds can change. Think of a box with a label.

The box labelled score starts at 0. You collect a coin and your program changes the score to 1.