Dynamo - Schematic DrawingElectricity
encompasses the principle that charged particles are attracted to each other. Most of the time we reference electricity specifically regarding the flow of electrons - and for our interests, we will stick to that.
So, what is the flow of electrons you may ask? Well, if we can remember back to our days in science and physics class, electrons are negatively charged particles which circle the nucleus of an atom. If we have the same amount of electrons (negative charge), and we have the same amount of protons (Positively charged) then the atom is said to be neutral. If there are more positively charged protons, then the atom is positively charged, and if there are more electrons, then the atom will be negatively charged.
In a conductor the atoms exhibit certain qualities that allow electrons to freely pass from atom to atom. Good conductors, such as copper allow this "electron flow" to happen with relative ease, whereas insulators (such as ceramics) make this process more difficult.
The study and use of this electron flow is called electricity and can be used in many ways. In computer chips and micro-controllers, electricity is used to transfer low powered signals for logic computations, while electricity can also be used to providing large amounts of energy to drive heavy equipment.
The laws of electricity are at work in almost every facet of robotics - from providing control logic, running sensors, and powering motors. Without electricity the field of robotics (and much else in our modern world) would not be possible.