Panning determines where a sound sits in the left-right stereo field. A vocal panned center appears to come from straight ahead; a guitar panned hard left appears to come from the left speaker only.
Strategic panning creates width, separation, and space in a mix. Common conventions: vocals, bass, kick, and snare stay centered; guitars, keys, and backing vocals are spread left and right; percussion and effects fill the stereo field.
The LCR (Left-Center-Right) panning approach uses only three positions for a bold, wide mix. The alternative — fine-tuned panning — places elements at precise positions across the stereo image.