Values & Variables

Try to imagine a program that can’t remember. You type your name into an app — and one instruction later, it’s gone. A game where the score can’t be kept. A shopping cart that forgets each item the moment you add the next. Useless, right? Programs are only useful because they can hold on to things while they work.

A variable IS that remembering. And it gives the remembered thing a name, so later instructions can talk about it: “add the price to the total” only works because price and total are names pointing at stored values. Every username on a screen, every score, every cart total you have ever seen was a variable in someone’s program.

This is the foundation everything else stands on. Every app you’ve ever used — WhatsApp, YouTube, a bank app — is at its core just values being remembered and changed. A value is one piece of data: the number 25, the text "hello", the answer true.

A variable is how a program remembers a value: the machine reserves one of its memory boxes, puts the value inside, and ties a name to the box — like a label on a jar. From then on, using the name means “go look in that jar.” That’s it. That’s the big secret.

Take this phase slowly. If variables, values, and types become truly obvious to you, every later phase gets easier — functions, objects, even Playwright tests are all built from these same jars.