Single coil pickups and humbucking pickups
Among many other variables, two things that affect the sound of the guitar are the type of wood used and the pickup system that the guitar is fitted with. Two popular choices are single coil pickups and humbucking pickups. Single coils (like the pickups fitted on most Stratocasters) tend to produce a bright and more articulate sound that doesn’t take up a lot of space in a mix, where Humbuckers produce a thicker sound that can overpower other mid-range instrument sounds or even other guitars.
Humbuckers are typically the type of pickups used to get the ‘wall of guitar’ sound used in a lot of heavy metal music. Single coil pickups play nice with a guitar amp’s overdrive channel and are what gives the Fender stratocaster its’ distinctive ‘quack’ in blues music.
Although with their respective tones aside, these pickups serve two very different functions. Single coil pickups are more succeptable to electromagnetic interference while humbuckers are designed to reject these types of interference. This gives a more noiseless guitar signal especially when using a really thick distortion and the heavier tone is an afterthought. They can also go a long way towards helping control feedback (I say control because they can be used in your favor to both generate and eliminate feedback).