Question 1

What rule does Langton's Ant follow?

Accepted Answer

The canonical two-colour rule from 1986: on a white cell the ant turns 90° right, flips the cell to black, and moves forward; on a black cell it turns 90° left, flips the cell to white, and moves forward. Nothing else · every pattern you see emerges from those two lines.

Question 2

What is the famous "highway"?

Accepted Answer

After roughly 10,000 steps from an empty board, the ant abruptly stops looking chaotic and starts building an endless diagonal corridor of 104-step cycles · the highway. Nobody has proven why it always appears, which is part of what makes this tiny automaton famous. On this board the edges wrap around, so the highway keeps travelling instead of stopping at a corner.

Question 3

How do I change the board?

Accepted Answer

Tap or click any cell to flip it between white and black · the ant reacts to whatever it finds. Then press Play to run, Step to advance one move, Reset to restore the current starting board, and drag the speed control up to a bounded maximum. The Sprinkle button seeds a fresh random scatter of black cells.

Question 4

Does it keep running when I leave the tab?

Accepted Answer

No. The simulation pauses when the tab is hidden or backgrounded, so it never burns battery in the background. When you return, it stays exactly where you paused it · the step count and board are preserved.

Question 5

Does it respect reduced motion?

Accepted Answer

Yes. If your device requests reduced motion, the board does not auto-animate. Everything still works · you step the ant by hand with the Step button or the Right arrow key, and the current state is always visible without any animation.