Introduction to Variables

In this lesson we'll get acquainted with variables in C++. Variables are the basic building blocks of every program, because they allow us to store and work with data.

Imagine a variable as a box where you can store some value:

• The box has its name (variable name)
• It can contain a certain type of value (number, text, ...)
• We can change the value in the box at any time
• We can look at what the box contains at any time

For example in mathematics we use variables like x or y. In programming it's similar, but we can give them any meaningful name:

int age = 25;           // Variable for age
double height = 180.5;  // Variable for height
string name = "Karel";  // Variable for name

Variables allow us to:

• Store calculation results
• Remember user input
• Track program state
• Work with data repeatedly

In the following exercises we'll learn how to create variables, change their values, and work with different data types.