| A | B |
| Circuit | the pathway through which electric current flows |
| closed circuit | a complete, circle-like pathway through which electricity moves |
| open circuit | a circuit with either a break in it or with a nonconductor interrupting the pathway |
| battery | an electrochemical source of electricity |
| series circuit | a single pathway through which electricity can flow |
| parallel circuit | a circuit in which there is more tha one pathway through which electricity can flow |
| insulator | anything that electricity cannot move easily through; resistance |
| conductor | a thing electricity can easily pass through; metals & electrolytes |