Random-access memory (RAM) is where programs and the systems that run the computer are stored until the CPU can access them. RAM may be read and altered by the user. In general, the more RAM, the faster the computer. RAM holds data only when the current is on to the computer. Newer computers have DDR (double data rate) memory chips. Read-only memory (ROM) is memory that can be read, but not altered by the user. ROM stores information, such as operating programs, even when the computer is switched off.