You first heard the use of pitch correction in a big way on Cher's 1998 hit "Believe." Variously referred to as Auto-Tuning, the Cher Effect or the T-Pain effect
(this latter artist is a rapper who popularized the sound), all of these styles are described here in this book and accompanying DVD-ROM.
Since Cher first put the audio effect on the map, pitch correction - making sure a singer is in tune and on key - has become a major part of recording.
Gone are the days when a singer would step up to a microphone and go over and over a part until it was pitched properly and in the pocket. Now, by utilizing one of the many tools described here including the abovementioned T Pain Effect, there is Nectar and, for polyphonic pitch correction, Celemony's Melodyne DNA.
Like any other recording device, before you can individualize an effect, you first need to know everything about how it works. You can learn all of that from author Max Mobley, a product and support manager for E-Mu Systems, Inc.
and a product manager for Antares Audio Technologies, the developers of Auto-Tune. The accompanying DVD-ROM provides tutorials on the written material, which include insights and special tricks in manipulating the sounds.