This is top level listing for IC Memory manufacturers.

The listing is divided up into Volatile ICs and non-Volatile IC memory.

Volatile Memory does not retain its data once power is lost. Volatile memory are primarily the RAM style memory.
In some cases RAM memory may be used in applications where prime power is removed and data needs to be retained.
In these limited cases a battery is used to supply power to the RAM.

Non-Volatile Memory will retain its stored contains even when no power is applied.
Non-Volatile memory is primarily the ROM style of memory

IC Memory Acronyms, Memory terms and memory definitions.