Turn on a light, pop some toast in the toaster, electricity is there and ready to go to work for you. But what exactly is it? To find out, you have to get really small. You have to go down to the atomic level.
An electron is a negatively charged particle in an atom. Everything (you, your desk, a cheese sandwich) is made of atoms. These atoms contain electrons, particles with a tiny negative electric charge. In some materials, electrons can jump from atom to atom. But to start the electrons jumping, there needs to be an imbalance. There needs to be more electrons at one end of the conductor than at the other.
In a battery, for instance, the negative pole has lots of electrons and the positive pole has few. When you connect the two poles through the circuitry of a device like a flashlight, the electrons have a path they can use to flow from the negative to the positive pole to correct the imbalance. This is what we call "electric current." In this example, we get the electricity to do some work—lighting a bulb.
You've probably experienced electricity yourself. Ever touch a door knob and get a shock? In this case, there was an imbalance of electrons between you and the doorknob. In an instant, this imbalance was corrected.