Generally, though, we place a device in the circuit that prevents the charge from moving easily. The way that I like to think of this is like a stream flowing down a hill. The battery consists of a guy with the bucket which takes water up to the top of the hill and pours it back into the stream. The current is the current of water flowing down the stream. If the stream has alot of boulders in it, it is difficult for the water to flow, and it takes it longer to get to the bottom of the stream.
Water backs up, and the battery has to get the high pressure hose to keep the current flowing.
This device is called a resistor . It has a mathematical property called resistance which relates it's difference in potential and the charge flowing through it. This is a puzzling question. There are generally 3 or 4 stripes on the resistor. The first two represent the values of the ones and the tens digit of the resistor, and the 3rd represents the exponent of the multiplier.