What is fuzz?
Fuzz is a distorted sound that often is described as warm and round, but still dirty, or just "fuzzy". Early pedals, like the original Fuzz Face, used germanium transistors to get that warm sound but some years later manufacturers started to replace them with silicon transistors. However, many guitarists have found these units less cripsy and a little harsher, but there's fans to each of these systems. Also, the quality of different pedals may vary, as the tolerance on germanium transistors can be very different.
Any good examples?
In the middle of the ninetyfifties guitarists evolved a passion for fuzz. It was first derived from faulty or damaged speakers, often because of transportation accidents. Surf rockers Link Wray and Dick Dale were pioneers, but the sound really took off after the 1964 hit single "You Really Got Me" by The Kinks. The guitarist in the band, Dave Davies, used a razor blade to slash his speaker cones to achieve this tone. A year later Keith Richards of The Rolling Stones experimented with one of the first fuzz pedals, the Gibson Maestro FZ-1, when he recorded a guideline for how the horn section should play on the song "(I Can't Get No) Satisfaction". There never got to be any horn section on this song - the fuzzy guitar riff sounded too good! Some years later Jimi Hendrix and Carlos Santana joined in and showed the world how a fuzz box could, and should, sound. Listen to "Spanish Castle Magic" (Hendrix) or "Evil Ways" (Santana) for great examples.
Which pedal should I get?
Jimi Hendrix relied on a Dallas Arbiter Fuzz Face (re-issued by Dunlop) which is a classic unit. Another early pedal which has earned much praise is the Electro-Harmonix Big Muff PI, a pedal that has been used everyone from Santana to Thin Lizzy to the alternative rock wave in the late eighties with bands like Smashing Pumpkins, Dinosaur Jr and Mudhoney (who even named one album, "Superfuzz Bigmuff", after it). Other great units are the Voodoo Labs Superfuzz, Roger Mayer Voodoo Axe, Zvex Fuzz Factory and the Boss FZ-5 (a digital unit which can mimich three classic fuzz pedals).