An algorithm is a set of step-by-step instructions for solving a problem or completing a task. Think of it like a recipe: first you do this, then you do that, and if something specific happens, you do something else. Algorithms tell computers exactly what to do, in order, to accomplish something.

When you follow the long division steps in math class, you're using an algorithm. The steps always work the same way, no matter what numbers you're dividing. Computer programmers write algorithms to tell computers how to sort a list of names alphabetically, recommend videos you might like, or figure out the fastest route to your friend's house.

Today, algorithms run nearly everything digital: they help search engines find websites, social media apps choose what posts to show you, and video games decide how characters should move. Some algorithms are simple, with just a few steps. Others are incredibly complex, with millions of instructions working together.

When people talk about “the algorithm” deciding what videos appear on a website, they mean the specific set of rules that a computer program follows. A good algorithm solves problems efficiently and accurately. A poorly designed algorithm might work but take forever, like alphabetizing your class by checking every possible arrangement instead of using a smart system.