The Fission Theory: This theory proposes that the Moon was once part of the Earth and somehow separated from the Earth early in the history of the solar system.
When you actually use that class to make a THING, this is what you make. A method is a bit of code that can be called when needed (often as part of an class, but not always) Here's an example: I write a class called Ball. In my main code, I then write a=Ball.new, b=Ball.new, c=Ball.new.
An update to the above answers, I agree instance methods use an instance of a class, whereas a class method can be used with just the class name. There is NO more any difference between instance method & class method after automatic reference counting came to existence in Objective-C.