Variables and Data Types

Variables and data types are fundamental concepts in programming. They appear in almost every programming language and form the foundation of how programs store and process information. Although the syntax may differ between languages, the core ideas remain the same.


What You Will Learn in This Section

This section is divided into smaller parts to make learning easier and more focused:

1. Variable

Learn what a variable is, why it exists, and how values are stored and updated in a program.

2. Data Types

Understand the different kinds of values that variables can hold, such as numbers, text, and logical values.

3. Variables and Data Types Together

See how variables and data types work together to form meaningful data in real programs.


Why This Matters

Variables and data types are used everywhere in programming.
A strong understanding of these concepts will help you:

  • write clearer code
  • avoid common beginner mistakes
  • understand later topics more easily

Take your time with this section. These ideas will be reused in almost every topic that follows.


Table of contents


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