The document provides an overview of PHP variables, including how to declare them, their scope (local and global), and the use of static variables. It outlines naming rules such as starting with a letter or underscore, case sensitivity, and mentions reserved words that should be avoided in variable naming. Additionally, it offers a brief example of declaring and using variables in functions.

1. PHP Variables

2. TOC Declaring variables Variable scope Static Variable Reserved words

3. What is a variable Stores value myName is “Joe” is $myName = “Joe”; //strings UserId is 086AFTG is $UserId = 086AFTG; // numbers

4. Rules of PHP Variable naming starts with a letter (A-Z, a-z) or underscore (_), followed by any number of letters, numbers, or underscores. variable name is case-sensitive. So $MyName and $MYNAME are not same. You don’t need to mention what kind of value you are going to store.

5. Variable Scopes Local Scope function myFunction () { $FirstName = “Joe”; // local //do something } Global Scope $department = “Marketing”; // global function myFunction () { $FirstName = “w3resource”; //do something }

6. Static Variables function test_count() { static $x=1; echo $x; $x++; } test_count(); test_count(); test_count(); //Displays 123

7. Reserved Words Cannot be used as constants, class names, function or method names. May be used as variable names, but confusing so avoidable. Examples: case, namespace, __METHOD__ etc.

8. Further Reading W3resource PHP Variables Tutorial PHP : Variables - Manual