Early console games either used a password based saving system or none at all. Later on, certain games (Final Fantasy for example) had a small battery, allowing game data to be saved aboard the cartridge's RAM. Save points were used because at the time, it wasn't possible to allow on-the-fly saving on most console games because of the game state being too complex or large for the game's memory/card/whatever. This mechanic is a perfect example of something created through technological limitation, carrying through games today.
