What is Algorithy

Algorithy is a browser game that teaches algorithms by play. Think of it as a puzzle game where the pieces are instructions.

The story in one screen

A little mouse stands on a grid. Somewhere on that grid is a piece of cheese. Your job is to get the mouse to the cheese. You do not steer the mouse with arrows or a joystick. Instead you build a small program out of blocks:

• move-forward - take one step in the direction the mouse faces.
• turn-left / turn-right - spin the mouse in place.
• repeat (for) - do something a chosen number of times.
• while - keep doing something until the mouse reaches the cheese.
• if / else - do something only when a path is open (or closed).
• switch - pick one of several paths depending on what the mouse sees.

You drag these blocks from a palette into a program area, press Run, and watch the mouse walk, turn, slide over ice, and (hopefully) arrive at the cheese. If the program is wrong, the mouse stops, bumps into a wall, falls in a hole, or keeps going forever; you fix the program and run again.

Where the idea comes from

The game follows the structure of Code.org's "Hour of Code" maze (level 1 of 20): short levels that each teach one new idea, starting with a single move-forward and ending with a maze that needs loops and decisions. The teaching trick is the same one that makes Scratch work: instead of typing code, you snap visible blocks together, so the syntax can never be wrong. Every mistake you can make is a thinking mistake, and thinking mistakes are exactly what the game wants you to practice.

What the game teaches, level by level

Each level introduces one concept and only offers the blocks needed for it:

The full table is on the Levels overview page.

What makes it different from a video

The game is not just an animation. Under the hood there is a real simulator: the same code that walks the mouse on screen decides whether you won. It counts cycles (a rough measure of how much work your program does), so a shorter, smarter program scores better than a long one, and it explains why you lost: blocked by a wall, never reached the cheese, stepped into a trap, or looped forever. All of that is described on the Simulation and Cycles and optimization pages.

What you can do besides solving levels

• Export as code: the game turns your blocks into real C, Python and JavaScript, so you can see what you actually "wrote". See Code export.
• Pick a language: the whole interface works in English and Serbian. See Internationalization.
• Change the mouse: two skins, blue and pink.
• Pick a level freely: a level picker lets you jump anywhere, and your progress is remembered in your browser.

And what it deliberately is not

• There is no server API. The game runs entirely in your browser; the server only hands out the files.
• There is no account and no cloud. Progress lives in localStorage in your own browser.
• There are no ads, no timers, no violence. The mouse walks, slides, and when it fails it falls into a cartoon pit or vanishes in a puff; the art is deliberately soft and friendly.

Ready to run it? Go to Getting started.