Variables

Variables

In this tutorial, we'll store values with clear names and reuse them in code.

A variable is a name that points to a value. You use variables when you want to store information and reuse it later.

name = "Aisha"
age = 12

print(name)
print(age)

Here, name points to the string "Aisha", and age points to the integer 12.

Why Variables Are Useful

Without variables, you repeat values everywhere:

print("Maya scored 8")
print("Maya needs 2 more points")

With variables, the code becomes easier to change:

student = "Maya"
score = 8
points_needed = 10 - score

print(student, "scored", score)
print(student, "needs", points_needed, "more points")

If the score changes, you only change one line.

Naming Variables

Good variable names describe what the value means:

temperature = 21
first_name = "Ben"
is_logged_in = False

Poor names make code harder to read:

x = 21
a = "Ben"
b = False

Short names are fine for tiny examples, but real programs are easier when names are clear.

Reassigning Variables

Variables can point to a new value later:

score = 0
print(score)

score = 10
print(score)

Python runs from top to bottom, so the second assignment replaces the first one.

You can also update a variable using its current value:

score = 10
score = score + 5

print(score)

This means: take the old value of score, add 5, and store the result back in score.

Common Mistakes

Variable names cannot contain spaces:

first name = "Ada"  # wrong

Use underscores instead:

first_name = "Ada"

Variable names are case-sensitive. score, Score, and SCORE are three different names.

Practice

Create variables for a product name, price, and quantity. Print a sentence that includes all three values.