# Boolean Expressions¶

A Boolean expression is a question that has two possible values or outcomes, either a “True” or a “False” (or you can look at it as a 1 or a 0). An example of a Boolean expression is, “A Volkswagen beetle is a car.” Clearly this statement is true, so that is how it is evaluated to “True”. You could also have, “A frog is a mammal.” This statement is not correct, so it evaluates to “False.” You could also have mathematical expression, “3+2 = 6.” This equation (and yes it is an equation so you read the “=” as “is equal”) is not correct, so it is also evaluated to, “False.” There are many other types of expressions that can be checked, besides equality. You could have an inequality like, “3+2 <= 6.” This time the inequality is evaluated as, “True” since 5 is less than or equal to 6. Some of the most common operators for Boolean expressions in computer science are:

Operator |
Meaning |
---|---|

== or eq |
Equal to |

< |
Less than |

> |
Greater than |

<= |
Less than or equal to |

>= |
Greater than or equal to |

<> or != |
Not equal to |