Data types tell us a few things about a piece of data, like:

• How it can be stored
• What operations we can perform with it
• Different methods it can be used with

Data types are present in all programming languages, but are particularly important in C#. That’s because C# is known as a strongly-typed language—it requires that the programmer specify the data type of every value and expression. While it means writing more code, using types has long term benefits like built-in documentation and increased readability.

As we can see to the diagram to the right, C# has several built-in data types. You don’t need to memorize all of them, but pay specific attention to these common ones that we’ll use throughout our lessons:

• int - whole numbers, like: 1, -56, 948
• double - decimal numbers, like: 239.43909, -660.01
• char - single characters, like: “a”, “&”, “£”
• string - string of characters, like: “dog”, “hello world”
• bool - boolean values, like: true or false