Variable

A variable is a named storage location in memory that holds a value. You give the variable a name, assign a value to it, and then use that name whenever you need that value.

Think of it like a labeled box: the label is the name, and whatever is inside is the value.

 ┌─────────┐
 │    1    │  ← value
 └─────────┘
    score    ← name

When the program runs, it looks up the variable’s name and retrieves the value stored inside.

Why Variables Matter#

Without variables, a program forgets information as soon as it moves to the next line. Variables let you hold on to values — like what the player typed — so you can use them later.

Declaring a Variable#

To use a variable, you first need to declare it. Declaring a variable tells the program: “I need a storage location with this name.”

Changing a Variable’s Value#

Once declared, you can update the value stored in a variable by assigning a new one to it. The old value is replaced.

int score = 0;
score = 1;
score = 0
score = 1
let score = 0;
score = 1;

After the second line, score holds 1.

Resources#