I suppose I have perfect pitch, in that I can more often than not: * aurally identify key signatures * aurally identify chords * sing a given note on command It wasn't until I was into my early twenties that I could do this. For me, the single biggest stepping stone was building the connection between what I could hear in my head from a song that I remember clearly with the underlying music theory. Specifically, buil…
My understanding of true, perfect pitch is something a bit more innate. Individual with perfect pitch do not need to rely on any other techniques.
I've known people with both types. If anything, the practical differences are not significant enough to truly matter from my observations. Many of the folks with true, perfect pitch have told me that it is a curse more than a blessing. These people tend to hear notes even when they do not want to e.g., toilets flushing in an out of tune C, the pitches in people's voices, the pitches of jet engines, CPU coil whining in D#, etc..
When a lot of modern life is constant noise and out of tune, it can be somewhat distressing for people with perfect pitch, or at least, so they have told me. I can't imagine turning off a song on the radio solely because it's a few cents out of tune, but hey, I knew people that would.