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PHP Boolean Variables

This tutorial will cover boolean variables in PHP.

What is a variable?
A variable is a piece of information which holds a value. Each variable has a type and a reference name. The value of a variable will depend on the type for that particular variable.

What types can a variable be?
There are a few different basic types of variable which include;

Strings hold characters, letters, numbers and symbols in a string format (essentially a character array), Booleans hold a true or false value and Integers hold a full number.

When are booleans used?
Booleans are used to determine if something is true or false and as such it can only hold a 'true' or 'false' value. Booleans are used in statements such as the if and else.

Bool is the shorthand version of Boolean.

Creating a boolean variable named 'bool':

  1. $bool;

Creating and initializing a boolean variable named 'bool':

  1. $bool = true;

Checking if bool is true, and if it is outputting 'Yes':

  1. $bool = true;
  2. if ($bool) {
  3. echo 'Yes';
  4. }

Checking if bool is true, and if it is outputting 'Yes'; the below code would NOT output:

  1. $bool = false;
  2. if ($bool) {
  3. echo 'Yes';
  4. }

Even though our boolean is not a string, we can still output the value. However; if it is true, it will be a string value of '1'; and a '0' if it is false:

  1. $bool = true;
  2. echo $bool;

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