Declaring variables

Learn to declare variables of type int, double, char and float.

Declaring variables

In C, a variable is a named memory location that stores a value. To declare a variable, you write the type first, then the name:

int age = 25;
double height = 1.75;
char letter = 'A';

Common types: int (integer), double (decimal), char (character), float (single-precision decimal). You can assign the value at declaration or later.

Multiple variables

You can declare multiple variables of the same type in a single line:

int a = 1, b = 2, c = 3;

Or assign the value later:

int x;
x = 10;

Local variables declared without an initial value are uninitialized; always assign before reading. As a good practice, give a value at the moment of declaration.

Exercise Declare and print a variable

Declare an int variable, give it a value, and print it with printf using the %d specifier.

Show example solution

#include <stdio.h>

int main(void) {
    int age = 25;
    printf("%d", age);
    return 0;
}

Test yourself

Which is an integer type?
- double
- char
- void
- int
Show answer

int — int is the type used for integers.
Assignment operator
```
int age ____ 25;
```
Show answer
```
int age = 25;
```
Match the types

int

Integer
double

Decimal
char

Character
float

Single precision

Next lesson: Variable assignment

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