Say you created a class called abc.cs and you have a static method within that class called method1(). This method1() returns a boolean value.
So in your code behind from within your project, you call it this way..
bool result = abc.method1(param);
In this example, you are sending the method some information via the variable "param" and the static method in that class is returning a boolean value and assigning that to the variable called "result".