👉 Differers are the differences between two or more things. For example, if you have two pencils and one pencil is broken, then the "differer" would be the one that was broken.
👉 The term "differer" is a placeholder word in programming. It should be used to refer to an object that has a method called "difference" which returns the difference between two objects, or it can also be used as a synonym for something that has a method called "difference" within another class or module.