Symbols

• ! (exclamation point), logical negation operator, Logical Operators
• != (exclamation point, equals sign), inequality operator, Comparison Operators
• !== (exclamation point, double equals signs), not identical operator, Comparison Operators
• # (hash mark), preceding comments, Shell-style comments
• $ (dollar sign)
  • preceding variable names, Variable names, Variables
  • in regular expressions, The Basics
• $$ (dollar signs, double), preceding variables containing variable names, Variable Variables
• $GLOBALS array, Global scope
• $this variable, Declaring Methods
• $_COOKIE array, Variables, Cookies, Cookies
• $_FILES array, Variables
• $_GET array, Forms, Variables, Processing Forms
• $_POST array, Forms, Variables, Processing Forms
• $_REQUEST array, Variables
• $_SERVER array, Server Information-Server Information, SSL, Navigating the Server Environment
• $_SESSION array, Session basics
• % (percent sign)
  • in format string, printf()
  • modulus operator, Arithmetic Operators
• %= (percent sign, equals sign), modulus-equals operator, Assignment with operation
• & (ampersand)
  • bitwise AND operator, Bitwise Operators
  • indicating value returned by reference, Passing Parameters by Reference, Return Values
• && (ampersands, double), logical AND operator, Logical Operators
• &= (ampersand, equals sign), bitwise-AND-equals operator, Assignment with operation
• (…) (parentheses)
  • enclosing subpatterns, Subpatterns
  • forcing operator precedence, Operator Precedence
• * (asterisk), multiplication operator, Arithmetic Operators
• ** (exponentiation), Arithmetic ...