Learn Electronics - Amperage and Voltage
Atoms are comprised of Protons, Neutrons, and Electrons. The protons and neutrons form the core of the atom and the electrons orbit rapidly around the core similar to the way our planets orbit around the sun. Electricity is the flow of "spare" electrons along things such as copper wire - pure copper wire is comprised of atoms of copper. Imagine a strand of copper wire laying on a table. If an electron is added to one end of the wire, it bumps an electron from the first atom of copper out of orbit. That electron then bumps another electron out of orbit from the next copper atom, which in turn bumps an electron out of orbit in the next copper atom... repeating the cycle all the way down the wire.
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Now that we understand the concept of amperage, we need to figure out what could possibly cause all these electrons to move through a conductive material such a as copper wire? Our eyes are incapable of seeing small things such as protons, neutrons, and electrons; while we accept that they are there, they are for all intesive purposes... invisible. So we know that there is this invisible force that must be pushing the electrons down the wire, but what could it be? The answer to that question is the term Voltage. Voltage is used to describe the potential force required to push elections from one atom to another.