# Comparisons

## Equality checking

A boolean is a value that is always 0 or 1, yes or no, on or off. In PHP, a boolean is represented by the words true and false. While programming, you will often want to know if something is positive or negative.

``````<?php

\$a = true;
\$b = false;
``````

There are many constructs and functions that will return a boolean. To start, let’s look at comparisons.

Double equals checks if two values are equal.

``````\$one = 1;
\$two = 2;

\$one == \$two; // returns false
``````

An exclamation point and equal sign check if two values are not equal.

``````\$one != \$two; // returns true
``````

You can use greater than and less than symbols to check for comparisons too.

``````\$one > \$two; // returns false
\$one < \$two; // returns true
``````

If you combine a greater than or less than symbol with an equal, it will check if the value is greater or less than or equal to another value.

``````\$one <= \$two;
\$one >= \$two;
``````

You can also check that two values are equal and of the same type by using three equal signs.

The following comparisons return true.

``````1 == 1;
1 == '1';
1 == true;
1 == 1.0;
1 === 1;
``````

These return false.

``````1 === '1';
1 === true;
1 === 1.0;
``````