Electrons are just really
negative people...
Picture Source: http://toonclips.com/600/cartoon-relaxed-white-guy-floating-while-meditating-by-ron-leishman-55645.jpg
The modern definition of an electron is that it is "a negatively charge subatomic particle. It can be either free(not attached to any atom), or bound to the nucleus of an atom" (WhatIs.com). In electric circuits the materials used allow for these electrons to move somewhat freely. Where as this is probably what is going on, it doesn't help a regular person understand what an electron is.
Imagine a group of people in a large open field. These people are super negative and no fun to be around. Because of this, they tend to try to stay as far away from eachother as possible. For example when one person moves to the left, another person will move to the left to stay away from him. This group of sour people is the McArthur theory's example of electrons.