Functions and methods can be used interchangeably, though there always are key differences.
We will focus on functions, and call it that from now on. Functions are self-explanatory in that they perform some sort of functionallity in the the program. 

The simplest example would be that of the functionality behind a button. In Python, we define functions like this:

	def buttonFunction():
		do something

The function is started with 'def' , for define, and followed by the name of the function (remember it has to be unique), a closed paranetheses(used for paramaters, if you have any) that must be there, and a colon.

Spacing in Python is very important. 
Anything inside the function must be nested within it, meaning it must be properly spaced from where 'def' begins. So, under proper format, 4 spaces to the right
Anything within the function cannot start on the same column of the 'd' in 'def' - that is the first requirement. Second, any other naturally nested statements must
also be spaced a column over from whats in the line above. It doesn't have to be 4 spaces, just 1, but by convention, it's 4 to keep things organized and readable. 
So for example: 

	def buttonFunction():
		if something: 
			do something
 
As you can see, the 'do something' is further in under the if statement. It cannot start on the same column as the i in if.

Just remember that everything must follow the proper syntax spacing. Anything written under the def function and spaced off to the right is considered part of that function. 
You exit that function by starting your next line of code on the same column of the d in def so for example I will write two separate functions in one program: 

	def function1():     
	 	print('one')
        def function2():    
		if 1 = 1:        
			print('two')

As seen above, two sep functions, both beginning on the same column with their inner functionality spaced off to the right. 

Side note: You can define a function within a function, it would be spaced off to the right like any other statement under the parent function, but that is a more advanced topic!