PCM & co. The differences?

[Deepest sound]

Hello,
Can someone teach me the differences between these types of PCM?
PCM (Pulse Code Modulation), DPCM (Differential Pulse Code Modulation), ADPCM (Adaptive Differential Pulse Code Modulation) and most of all LPCM (Linear Pulse Code Modulation).

[Tuti]

Re: PCM & co. The differences?

Its easy.

PCM works with a constant size of data (packets, pulses)
DPCM woks with the diferencial size of the data of the previous packet (pulse)
ADPCM (Adaptative) have no constant size of data and the size is adapted for the best size and quality with diferencial of previus packet

Sorry, but i have a bad english