A chunk of memory on a hard driveA type of persistent (non-volatile) memory built from rotating platters and “read heads” that sense the data on the platters. or SSDA memory that acts like a hard drive, but is built out of flash memory instead. that can be brought into DRAMStands for "dynamic random access memory." This is temporary working memory in a computer. When the goes off, the memory contents are lost. It's not super fast, but it's very cheap, so there's lots of it. for use or for execution.