Core PHP Programming: Using PHP to Build Dynamic Web Sites

Operators

An operator is a symbol that tells PHP to perform a mathematical or logical operation. Some operators expect two arguments, some only one. Most operators fall into three categories: arithmetic, logical, and bitwise. There are some exceptions, however. Table 2.4 lists the arithmetic operators.

Table 2.4. Arithmetic Operators

Operator	Operation It Performs
+	Addition
-	Subtraction and Negation
*	Multiplication
/	Division
%	Modulo Division
++	Increment
--	Decrement

Addition, subtraction, multiplication, and division are familiar concepts. They may be applied to integers or doubles. Using a string with an arithmetic operator causes the string to be converted to a number first. Modulo division returns the integer remainder of a division. The - operator ...