An algorithm is a list of steps, or instructions, that tells a person or computer what to do. It is a step-by-step recipe for solving a problem.
You already use algorithms every day: brushing your teeth, making a sandwich, tying your shoes, and following a recipe are all step-by-step instructions.
Computers follow algorithms to make decisions and do useful things, like sorting toys by color, finding the shortest path on a map, or deciding which video to show next.
Why do they matter? A good algorithm makes things happen in the right order, saves time and avoids mistakes, and breaks a big problem into clear steps.
Here is a real example. "How do I make toast?" Get the bread, put it in the toaster, press the button, and the toast pops up. Each step in order, and you get perfect toast.
Remember: an algorithm is just a set of steps, good steps are clear and in order, and both people and computers use them.
What to remember
- An algorithm is a list of steps to do something.
- Good steps are clear and in the right order.
- Computers follow algorithms to make decisions.
- People use them too, like following a recipe.
Words to know
- Algorithm
- A set of steps that solves a problem.
- Step
- One instruction in the algorithm.
- Order
- The sequence steps happen in; it matters.
- Input / output
- What goes in, and the result that comes out.
For grown-ups
An algorithm is a finite, ordered set of well-defined steps that turns input into output. It is the core idea behind all computation, from sorting and search to recommendations and routing. Clarity, correctness, and order are what make one work, the same discipline as a good recipe.
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