Storage Device (Memory): Kinds of Storage Devices:
The storage device is mainly known as computer memory. The device that stores the program or software is called a storage device/memory.
There are mainly two types of storage devices.
- Primary memory
- Auxiliary memory
Main memories are of two types-
- RAM (Random Access Memory)
- ROM (Read Only Memory)
Some storage devices are-
- Hard Disk Drive
- Compact Disk (CD)
- Floppy Disk
- Magnetic Disk
- Punch Tape
- Punch Card
- Pen Drive etc
- USB Hard Drive etc
What is the difference between RAM & ROM?
- RAM stands for Random Access Memory.
ROM stands for Read-Only Memory. - Ram is removable.
ROM is fixed with the motherboard.
- If electricity fails, all data of the RAM will be lost.
If electricity fails, all data of the ROM will be intact.
- RAM is used as a processing zone.
ROM is used to contain BIOS programs.
5. We can read & write in RAM.
We can read ROM only
6. Example of RAM:_Dynamic RAM, Static RAM
Example of ROM_PROM, EPROM
Describe Primary & Secondary storage memory
Primary storage device/memory: The memories that connect directly to the mainboard/motherboard are called main memory. Such as RAM, ROM. The data from input devices stay in primary memory for processing.
There are two types of primary memory.
- RAM 2. ROM
RAM:
RAM (or Random Access Memory) is temporary storage that can be read from or written into by the user. RAM is used primarily to store user programs and data. The content of RAM is generally volatile and is lost when power is removed. When the system is powered up. and data to be used must be read into RAM through an input device. Access time for data stored in RAM generally ranges from a microsecond to a few nanoseconds. RAM memories fall into two main categories (a) Static RAM & (b) Dynamic RAM.
According to slot, RAM Fall into two main categories
- SIMM (Single Inline Memory Module)
- DIMM (Double Inline Memory Module)
DIMM RAM fall into three types-
a. SD RAM (Synchronous Dynamic Random Access Memory)
b. RD RAM (Rambus Dynamic Random Access Memory)
c. DDR RAM (Double Data Rate Random Access Memory).
ROM:
ROM: ROM (or Read-only Memory) is used for storing programs and data permanently. The data and programs required for some applications are permanently stored in the ROM chip. Thus a user may read a program of data from ROM but may not write on ROM. The content of ROM is not altered when power is removed from the computer. It is therefore referred to as non-volatile memory.
ROM is generally used to store programs, routines, and language interpreters for immediate access by the user of the system. Such a program usually supplied by the manufacturer is referred to as firmware. Many microcomputers are supplied with ROM chips that contain the BIOS(Basic Input Output System).
Some ROM are- (a) PROM (b) EPROM (C) EEPROM.
Auxiliary Memory/Secondary Memory
This is generally much larger in capacity but is slower than the main memory. It is used for storing system programs and large files, which are not continually required by the CPU. Information in secondary storage is accessed indirectly via input-output programs. Common types of secondary memory are magnetic disk(Hard Disk), magnetic tape, and Optical disk (Compact Disk/CD).
