Imagine you have a little robot, and it will do exactly what you tell it — no more, no less. To get it to make you a jam sandwich, you can't just say "make a sandwich". You have to give it the steps, one at a time, in the right order:
A list of clear steps like this, that gets a job done, is called an algorithm. You already know loads of them! Brushing your teeth, tying your shoes, and getting dressed are all algorithms — little recipes of steps you follow to reach a goal.
Here is a robot on a grid. It can only understand two instructions: go right and go up. Our algorithm is a list of these steps that leads it to the star. Press play, or step through one instruction at a time, and watch the path appear.
So the whole algorithm is just: right, right, right, up, up, up. Six simple steps, and the robot reaches the star every single time.
Because the robot follows your steps exactly, the order you put them in changes everything. Swap the steps around and the robot ends up somewhere else completely — not at the star!
It's just like getting dressed. Putting on your socks and then your shoes works beautifully. Do it the other way round — shoes first, then socks — and you get in a real muddle. Same steps, wrong order, wrong result.
Yes! A computer has no common sense at all — it never thinks "hmm, that doesn't seem right". It does precisely what its algorithm says, in precisely that order. That's why the people who write algorithms have to be so careful and clear. A tiny mistake in the steps, and the computer will happily do the wrong thing without even noticing.
An algorithm isn't just "some steps" — the steps must be clear and in the right order. "Make a sandwich" is not a good algorithm, because the robot wouldn't know what to do first. "Spread the jam before the toast pops up" is a muddled order. Good algorithms leave nothing to guess and nothing out of place.