Power surges occur most commonly when you regain power to your place after a power outage or during the operation of high-power electrical devices such as air conditioners. Switching between devices that demand a large amount of power can upset the general voltage flow within your electrical system. When a power surge occurs, there is the possibility of your devices using less power to overload on electricity and be fried internally.
To better protect your smaller devices, use surge protected power strips. You can find them at your local hardware store or very easily online. You can find most surge protected power strips on Amazon between $5 - $20, depending on the number of outlets you're looking for & how long of a cord it has. This one is a great option: https://amzn.to/2QMirua