Methods are segments of the code that are called on to do certain tasks.Those tasks can be things like putting together a text representation of an object,  doing various computations or adding and removing things from lists. So, the majority of your code is going to be a made of methods. Some methods may be made for you in library classes like the Math.sqrt(int i) which returns the square root of a number.

A method is declared with:

public(private) (static) datatype methodName(<parameters>)

When a method is private it means similiar to when a field is private that it can only be used in it’s own class. Also unless the datatype is void a method has to return a value of that datatype this is done with:

return valueofDatatype;

Overloaded methods are when a method shares a name with one or more methods in that class but has different parameters, in this case the compiler determines which method you are talking about by using the parameters, so if you have a method g(int i) and method g(String i) its going to call the former if you put a int in as the parameter and to call the later the parameter needs to a string.

The link to the video focusing on methods, although i ran out of time near the end.