What religion is a CALVINIST ? Is it same as Presbyterian?

Sorry, no. 'Calvinist' is not a religion, it is a person who believes in one of John Calvin's main teachings of predestination. It is based on the acronym TULIP. You can find an explanation of TULIP from a Calvinist standpoint at: http://www.calvinistcorner.com/tulip.htm . While some Presbyterians might be Calvinists, by no means are they the same. Presbyterian is a denomination included in the 'religion' of Christianity, while being a Calvinist is a doctrinal belief. :) An honest mistake. One that no one I know would make, but an honest mistake.