What is the difference between RAM, DRAM, FlashRAM, ROM, SRAM…?
RAM stands for Random Access Memory. It is the designation for memory that can be both written to and read. ROM stands for Read Only Memory. ROM cannot be written to. It is used in the Newton for the Operating System. Hence you cannot delete it. SRAM stands for Static RAM. An SRAM cell consists of a small semiconductor circuit (a flipflop), that holds one bit of information. As long as power is supplied to this flipflop, it will retain its current state (unless changed intentionally, of course), hence the back-up batteries in SRAM cards. DRAM is for Dynamic RAM. A DRAM cell is constructed to be a tiny capacitor. It is much cheaper to manufacture, and can be much smaller. However, the capacitor will slowly lose it’s charge, hence the need to refresh it regularly. Also, the needed time to (un)load the capacitor in order to store a bit of information is significantly longer than the time needed to (re)set a flipflop. FlashRAM is based on EEPROM technology. It’s a kind of memory that does
