Beyond numbers and text, programs often need to represent simple "yes" or "no" states, like whether a light switch is on or off.

Rust has a specific data type for this kind of information.

Engagement Message

Can you think of a situation where you only need a true/false answer?

This data type is called a Boolean, named after George Boole. In Rust code, it's shortened to bool.

A Boolean variable can only hold one of two possible values: true or false.

Engagement Message

Why do you think these specific words are used?

It's crucial to remember that true and false must be all lowercase in Rust. True or False (capitalized) will cause an error.

Engagement Message

How is this different from storing the word "true" as a string?

Booleans are fundamental for decision-making in code. We often get Boolean values by comparing other values.

For example, we can check if two numbers are equal using == (double equals sign).