Repeating Steps with Loops

In computer science, doing the same thing over and over is called iteration. Instead of writing the same line of code a hundred times, programmers use a loop. A loop is a programming structure that repeats a set of instructions until a specific goal is met. Computers never get bored or tired, which makes them perfect for iteration! Whether it is a character walking across a screen or a music app playing a playlist, loops are working behind the scenes to keep things moving without making the code messy.

The simplest type of loop is the Count-Controlled Loop, often called a 'Repeat' loop. You tell the computer exactly how many times to do something. For example, if you want a robot to walk in a square, you could write 'Move Forward, Turn' four separate times. Or, you could use a loop to say Repeat 4 times. This makes your code shorter, easier to read, and much faster to fix if you make a mistake.

Sometimes we don't know exactly how many times we need to repeat. A Repeat Until loop (also called a conditional loop) keeps going until a certain 'condition' becomes true. For example, 'Repeat cleaning until the floor is shiny.' On the other hand, a Repeat Forever loop (or infinite loop) never stops! These are used for things that should always be running, like a clock checking the time or a game waiting for you to press a button.

What happens if you put a loop inside another loop? This is called a nested loop. Think of it like a clock: the 'seconds' loop repeats 60 times to finish one 'minute' loop. This allows computers to handle complex patterns, like drawing a grid or creating a wall of bricks in a game, by repeating a row multiple times.