Most are dedicated string trimmers, but Ryobi also makes a couple of 2-in1 string trimmers/edgers, a trimmer/brush cutter, and it also has weed wacker attachments for its Expand-It system.
When it's time to clean up the edges of your yard after mowing, edging the lawn with a weed whacker ... that's preloaded with string. Before you replace the line on your Ryobi string trimmer ...