Mowing is only part of the battle when it comes to maintaining a pristine lawn.
String trimmers are a vital tool in your arsenal of lawn-care weaponry.
Cut down unruly grass and weeds in and around gardens, trees, fences or other obstacles.
String trimmers come in two styles: electric or gas-powered.

Electric String Trimmers
Electric string trimmers are a good choice for smaller jobs. They lack the power of gas-powered models, but make up for that with their light-weight and maneuverability.
Electric string trimmers are powered by an extension cord so you'll need to be close to a power source. Also, they produce less noise than a gas-powered string trimmer.
Cordless String Trimmers

Cordless string trimmers are perfect for smaller jobs, away from an electrical source. Just charge up a battery, slap it in, and you'll be trimming right away.
One benefit of cordless electric string trimmers is you will not need to perform maintenance. No gas, no oil changes, no new spark plugs. Just trimming.
Gas-Powered String Trimmers

Gas-powered string trimmers are made for bigger lawns and are the choice of landscaping professionals. These are powerful and can easily mow down thick weeds and other brush.
Available with either 2-cycle or 4-cycle engines, these string trimmers are versatile enough to handle most jobs. Some models can be outfitted with attachments so you can not only trim, but edge, prune or cultivate as well.
Wheeled String Trimmers

Walk-behind wheeled string trimmers are capable of cutting down large amounts of grass in a short time. With a 22" cutting radius (1" larger than most walk-behind mowers), you can tackle overgrown areas quickly.
Wheeled string trimmers are perfect for rugged or rough terrain, as their large wheels allow them to easily roll around.