Since the inception of computer and other similar devices, there have been means of reading, writing and storing of data either for temporary use or future reference.
Where this data is written to is referred to as memory. Learn more about
meaning of computer memory. And we also have different types of memory such as primary, secondary e.t.c.
The primary memory is further divided into volatile (RAM) and non-volatile (ROM). However, in this article we are focusing on RAM. What then is RAM?
What is RAM?
Random Access Memory commonly shorten as RAM is a Read and Write storage hardware memory chip that is pre-installed on a device's motherboard as an internal memory to the device's Central Processing Unit.
Because of the volatile nature of RAM, it can't retain data written to it once the device is powered off. In other words, RAM needs the device to remain "on" for every data written to it to be retained. Therefore, once the device went off, every data written to RAM will be wiped and can't be restored.
Though RAM lost its data once the device goes off, it still has a unique advantage i.e data written to RAM can be easily access faster compared to ones written to HDD, Optical Drive, or SSD.
Furthermore, in determining the performance, speed of a device, the size and storage of the RAM are the most important factors to be considered. Hence, the device performance depends on the speed, size and storage capacity of the RAM.
It therefore means that the ability of a computer system to perform faster, access files and open programs quickly is solely dependent on the RAM.
History of RAM
Cathode Ray Tube RAM
The used of RAM was first seen in Cathode Ray Tube (CRT) and data was stored in electrically charged spots on the RAM's face. This RAM was introduced in the year 1947 with Williams Tube.
Magnetic Core Memory RAM
This was the second RAM invented in the year 1947. It is made up of tiny metal rings and wires connected to each of the tiny metal rings. Each of these rings is capable of storing one bit of data which can be access anytime.
Solid State Memory RAM
The solid state memory RAM was invented by Robert Dennard in the year 1968 at IBM Thomas J Watson Research Center. It is known to be a Dynamic Random Access Memory (DRAM) as well as has transistors that can store bits of data.
However, these transistors needs constant power supply to be able to retain stored data and also maintain the state of each transistors.
Intel 1103 DRAM
This was introduced in 1969 by Intel and it was the first commercial available DRAM.
Synchronous DRAM
This was introduced in 1993 by Samsung and became commercially available in 1996. It is known as the KM48SL2000 version
Types of RAM
The following are the two different types of RAM.
Both types of RAM are volatile, as both lose their content when the power is turned off.
1) Static RAM
A static RAM is a volatile memory that requires constant power in order to hold data stored or written in/to it. Unlike the Dynamic Random Access Memory that requires power to prevent leakage, SRAM does not require regular refresh as it doesn't need power for leakage prevention hence making it faster than DRAM.
Furthermore, one memory cell of SRAM can store up to one bit of data. Data is normally written to or stored in the transistors of the SRAM and it needs constant power supply to retain this data.
Features of Static RAM
Static random access memory has its importance as the memory of choice for cache memory. Here are some of its features.SRAM has a lower access time, around ten nanoseconds.It is much faster than DRAM as the memory cells do not require to be continuously refreshed.However, it consumes more power since it uses a bi-stable latch circuit, and requires a regular power source.It is costly and exists on the processors between the processor and main memory.It is long-lasting.As a part of the computer RAM, SRAM is entirely necessary but expensive
2) Dynamic RAM
Dynamic RAM is also a volatile storage device that requires constant power supply in order to keep or hold data written or stored in it. When storing data in DRAM, the data are directly stored in a cell that contains transistor and a capacitor.
Unlike the Static RAM, because DRAM stores data in cell that contains capacitors and transistors, it needs constant power supply in order to refresh it in every milliseconds, so that data stored can be retained and accessed.
Advantages of Random Access Memory
Some of the advantages of RAM are:
- It helps to boost the speed of the computer system during operation
- It allows read, write and delete operations to be executed
- It reduces data access time of the CPU as it makes it retrieve data faster than when communicating with hard drives, CD e.t.c.
- It does not consume much of the battery life
Disadvantages of Random Access Memory
The following are some disadvantages of RAM:
- It is expensive to acquire
- It is a volatile memory therefore data is lost once the system goes off
- It has a limited storage capacity
Characteristics of Primary Memory
The following are some characteristics of primary memory:
- It can only store data the computer is currently processing
- It is faster than secondary storage devices during data retrieval
- it contributes to the successful booting of every computer device
- Turning of the device clears out every stored data