Explain the developments ram since it was created in 1968 til today.

From DRAM to DDR4

Explanation:

RAM stands for Random Access Memory. In 1968, Mr. Robert Dennard at IBM's Watson Research obtained the patent for the one-transistor cell that will eventually substitute the old magnetic core memory allocated in computers of the time. By 1969 Intel released the TTL bipolar 64-bit SRAM (Static Random-Access Memory) as well as the ROM "Read Only Memory"; also in 1969 it evolved into "Phase - change memory - PRAM - ". However this evolution was not commercialized, Samsung expressed its interest in developing it. In 1970 the first DRAM product was commercially available; it was developed by Intel. In 1971 it was patented EPROM; in 1978 George Perlegos developed EEPROM.

By 1983 a nice breakthrough happened with the invention of SIMM by Wang Labs. In 1993 Samsung came up with KM48SL2000 synchronous DRAM (SDRAM), this variation soon turned into an inductry standard.

In 1996 DDR began a revolution in the memory sector, then in 1999 RDRAM. Both DDR2 SDRAM. DDRR3 and XDR DRAM were commercialized. Finally in 2007 and 2014 the developments of DDR3 and DDR4 were available for the general public.