140 likes | 548 Views
Storage device. Computer memory. Primary storage. Type of internal memory. There are two type of memory: RAM ( R andom A ccess M emory) ROM ( R ead O nly M emory).
E N D
Computer memory Primary storage
Type of internal memory There are two type of memory: • RAM (Random Access Memory) • ROM (Read Only Memory)
It is used by the computer to store programs and data that are currently being used;It is usually referred to as Computer’s RAM (Random Access Memory);It is also referred to as the Computer’s Immediate Access Store (IAS) Internal memory (RAM)
Internal memory can not hold all the data and programs that a computer might need;It only holds the data and programs that are in use at a particular moment in time, and empties and refills itself as different programs and files are used Internal memory (RAM)
Internal memory is volatile memory;This is because this memory is emptied (i.e its contents are lost) when the computer is turned off; Internal memory (RAM)
It is “Random” because any part of the memory can be accessed directly by the computer;RAM is made up of locations, also known as CELLS;Each location has a unique address that never changes. Internal memory (RAM)
When the computer is switched on, the operating instructions, computer programs, and data are moved into the RAM as required;RAM empties every time the computer is switched off – that is why work has to be saved before the computer is switched off!! Internal memory (RAM)
RAM is usually measured in “megabytes”;The more RAM a computer has, the more it can do. Random Access memory (RAM)
RAM is very fast compared to backup storage. It is about one thousand million times faster!That why a computer needs both a backup storage and RAM. It uses RAM for speed and the hard disk to store data whilst switched off. Random Access memory (RAM)
Read Only Memory (ROM) is not lost when the computer is switched off;All computers have a small amount of ROM;This is so that essential instructions can be stored, e.g Instructions to boo the computer. Internal memory (ROM)
Instructions stored in the ROM enable the computer to check the hardware and load the operating systems;Embedded computer systems usually have their programs stored i ROM;ROM are not as fast as RAMs Read Only Memory (ROM)