ABSTRACT: Carbonate platforms evolved to rimmed, shelf from ramp and isolated platforms they are drowned with time. Commonly, we can. observe a transition from one type to another, Residental commuties be haves mainly as sediment .producers and as bafflers» trappers, and binders.. Carbonate ramps may be developed at times of tectonic or climatic crises,. Homoclinal ramps, develop on gently regional paleoslopes. Ramps with fringing banks may develop on paleoslopes with higher gradients than those with barrier banks., Distally steepened ramps develop where earlier rimmed shelves undergo widespread drowning,. Rimmed corbonate... shelves are mostly develop on continental shelves in low-latitude areas,, where reefal biota are abundant. High rate of upbuilding commonly associated with reefal biota, increases relief and steepens the margin. Margins may change with time to accretionary, bypass and erosional margins. Isolated platforms develop on rifted continental and transitional crust. Most oceanic atolls develop on subsiding oceanic volcanoes, Platforms undergo incipient or complete drowning where sea level rise or subsidence exceeds upbuilding. After rapid sea level rise buildups and rims shows three buildup phases; as a lag phase,, a catch-up phase and a keep-up phase. On the passive margins, corbonate platforms commonly develop over rift volcanics, immature elastics and evaporites. On convergent margins,, they show different evolution pattern.., The progradation of the platforms may be stopped by the volcanism, subsidence of the margins, the falling of the sea level and naturally lasting up of system through the time.