- All the variables in PHP must start with a dollar ($) sign.
- The most recent assignment of a variable is its actual value.
- We use the “equals to” operator to assign the value to a variable.
- The variable name must start with a letter or underscore character. It cannot have characters like + , – , % , ( , ) . & , etc.
Now, let us create our first-ever variable in PHP.
<?php $number = 12345; ?>
The variable in the above example has an integer as value. Integers in PHP are whole numbers such as 12345. They do not have a decimal point. Both negative and positive whole numbers are classified as integers.
Similarly, we can also create a variable with a string as a value. A string is simply a sequence of characters. “PHP is an important programming language to learn” is a string. We always enclose strings in double or single quotes. The following is an example of a string variable.
<?php $string = "This is a string variable"; ?>
If you want to print these variables, you will simply use the echo function.
<?php $number = 12345; $string = "This is a string variable"; echo $number; echo $string; ?>
Now, the Apache will print the value of these variables on your screen.
Keep in mind that PHP is case sensitive which means CAPITAL and capital are totally different variables.
<?php $CAPITAL = "This is a totally different variable"; $capital = "capital is not the same as CAPITAL in PHP"; ?>
<?php $number = 12345; $string = "This is a string variable"; Echo $number . " " . $string; ?>
In the next lecture, we will study simple mathematical operators or how to do mathematics in PHP.