What is a difference between a method and a function?

Question

What is the difference between a method and a function? Is it that a method returns a value and a function doesn't?

Answer 1

Method is actually a function used in the context of a class/object.

When you create a function outside of a class/object, you can call it a function but when you create a function inside a class, you can call it a method.

class foo {    public function bar() { // a method      ........    } } 

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function bar() {  // a function not part of an object } 

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So an object can have methods (functions) and properties (variables).

Answer 2

The words are not opposed to each other but rather describes two possible aspects of a subroutine. An attempt to define the words follows:

Subroutine: A set of instructions that can be used several times in the same program.

Function: A subroutine that returns a value. Derived from functions in mathematics (wikipedia).

Method: A subroutine that belongs to an object or a class. Could be a function.

I tend to use the word "function" for every subroutine that has no side effects but returns one clear value and the word "method" for every subroutine that has a side effect.