Pickups are essentially small microphones that pick up the string's vibration and turn it into an electronic signal. The signal is then transported through to the instrument cable to the preamp where it is amplified and then sent out of the speaker. There are a number of different types of pickups each with different tonal characteristics. I’m going to explain what some of the more common pickups are and what they sound like.
Single Coil - Single coil pickups are most commonly found in Stratocasters and telecasters. These are considered high gain or “hot” and tonally would be described as clear, crisp and pinchy (depending on what position). A single coil pickup in the bridge position will generally be quite high gain and in the neck position, you will get more bass and mids. While these pickups are known to have a bit of extra noise when compared to humbuckers that should not deter you because they have a very unique tone that can’t be truly replicated by any other style of pickup.
Humbuckers - Humbucker pickups are made up of two single coil pickups wound together in opposite positions, reverse polarity or “out of phase”. This style of pickup makes for a very quiet pickup in terms of excess sound and Bucks the hum, as per the name Humbucker. While it cancels out the external noise it also has a very well rounded large tone. These are most commonly found in Les Pauls, SG’s, sometimes telecasters and many more guitars.
P-90s - P-90 pickups are the predecessor of humbuckers. They were produced in the Gibson factory and were found in a lot of the early 50’s Les Pauls. P-90s are known to be quite a gritty and gainy pickup. While these look quite similar aesthetically to the humbuckers these pickups are actually single coil.