What are variables?
The variables are used as containers, like boxes, where we can keep values.
Their names should always have the $ symbol at the beginning, followed by a letter or "_" (underscore). After that you can either use letters, numbers or underscore, like "$first_name" or "$_address1". Beside underscore no other special characters (like "+, -, *, % ...") are allowed for the name.
The names are case sensitive (PHP makes the difference between uppercase and lowercase letters of the name), so PHP will see "$movieName" as one variable and "$moviename" as another variable.
<?php //examples of variables $first_name = 'Edward'; $description = 'This is a PHP course'; $month_number = 11; ?>
Which variable names are correct?
As their names suggests ("variables") we can change the content of a variable as many times as we want, the content is variable. We can also assign the value from one variable to another one.
<? $fruit = 'apple'; $fruit = 'mango'; $tropical_fruit = $fruit; //it will display the value 'mango' echo $tropical_fruit;
The semicolor symbol ; is required to signal the end of an line instruction.
We use echo when we want to output a value.
How many times we can change the value of a variable?