parallel circuit is one type of circuit in common house hold. The following graph shows a parallel circuit:
R1 and R2 are two resistors and the connection is a parallel connection, which means different loads are situated on different loops, the voltage on R1 and R2 will be the same, and if R1 is removed, R2 will keep on working. Or when R2 is removed and R1 will also work. In parallel circuit, the current is splitted up. In other words we can add up the current goes through R1 and current goes through R2 to get the total current. The danger of connecting too many power hungry electronic devices on 1 power strip is that the current will get very high, if you are lucky to have a circuit breaker, the circuit will cut off so it won't cause a fire.