Power surges, or moderate voltage changes, occur regularly. Voltage spikes, or sudden peaks of power, can cause equipment malfunction and premature circuit failure.
Noise interference can cause information loss.
The surge protector guards data and equipment by filtering electrical power. It acts as a shock absorber by limiting damaging power fluctuations. It is life insurance for your computer. If your computer is attached to a telephone line for modem or fax use, you should surge-protect the phone line too, since lightning strikes to telephone lines are not uncommon. We've seen it happen, and it's not pretty.