An electric current is a flow of electric charge. The flow or movement of charge is usually driven by a difference in potential. So the current is 2A. Currents are driven by differences in potential, often called a voltage or a voltage difference. If the potentials are different, the electric force pushes the charge between them. There are several ways of producing potential differences.
Batteries do it chemically, chemical reactions produce the potential difference.
The symbol for a battery is shown at the right. The potential difference is measured in Volts, and is sometimes called the Voltage. A typical circuit would look like the one at the right. In-between the terminals of the bulb is another metal wire, usually not as good a conductor as copper. To do this the battery does work on them.