Memory and hard disk are two essential components of a computer system. Memory refers to the temporary storage used by a computer to perform its operations, while a hard disk is a permanent storage device used to store data and programs.
1. Memory: Memories are made up of registers. Memory refers to the location of short-term data. Each register in the memory is one storage location. The storage location is also called as a memory location. Memory locations are identified using Address. The total number of bits a memory can store is its capacity. Memory is of three type: Primary Memory, Secondary Memory and Cache Memory.
Types of memory include:
- DDR (Double Data Rate) RAM: DDR RAM is the most common type of memory used in modern computers. It is fast and efficient, providing high-speed data transfer rates.
- SRAM (Static Random Access Memory): SRAM is a type of memory that is faster than DDR RAM, but also more expensive. It is often used in high-performance computing applications.
- SDRAM (Synchronous Dynamic Random Access Memory): SDRAM is a type of memory that is synchronized with the computer’s clock speed. It is commonly used in desktop and laptop computers.
Features of memory:
- Volatility: Memory is a volatile form of storage, which means that the data it contains is lost when the computer is turned off. This is in contrast to non-volatile storage, such as a hard disk, which retains data even when the power is off.
- Capacity: The capacity of memory refers to the amount of data that can be stored in it. Memory capacity is typically measured in gigabytes (GB) or terabytes (TB). The more memory a computer has, the more data it can store and process.
- Speed: Memory is much faster than other forms of storage, such as a hard disk or solid-state drive. This is because memory has no moving parts and can access data quickly.
- Access time: The access time of memory refers to the time it takes for the computer to access a particular piece of data in memory. Access time is typically measured in nanoseconds (ns). The lower the access time, the faster the memory.
- Type: There are different types of memory available, each with its own set of characteristics. For example, DDR (Double Data Rate) memory is the most common type of memory used in modern computers, while SRAM (Static Random Access Memory) is faster but more expensive.
- Error correction: Some types of memory include error correction features, which help to detect and correct errors in data. This is important for ensuring the accuracy and reliability of data stored in memory.
2. Hard Disk: Hard Disk is a magnetic disk made of aluminum. It is used as the main storage device on the computer. It uses a metallic disk which is known as platter. Both sides of disk is used for storing data except the upper side of the uppermost disk and lower side of the lowermost disk. Magnetic oxide is used to coat the data storing surface.
Features of hard disks include:
- Capacity: Hard disks come in a variety of sizes, ranging from a few gigabytes to several terabytes of storage capacity.
- Speed: The speed of a hard disk is determined by its rotational speed, measured in revolutions per minute (RPM). The faster the RPM, the faster the hard disk can access data.
- Interface: The interface of a hard disk determines how it connects to the computer. Common interfaces include SATA (Serial ATA), IDE (Integrated Drive Electronics), and SCSI (Small Computer System Interface).
- Form Factor: The form factor of a hard disk refers to its physical size and shape. Common form factors include 2.5-inch and 3.5-inch hard disks.
Difference between Memory and Hard Disk :
| S.No. | MEMORY | HARD DISK |
|---|---|---|
| 1 | It is an electronic component that is capable of storing data and information. | It is magnetic disk made of aluminum and used as main storage device of computer. |
| 2 | It needs a continuous power supply to hold the data. | It doesn’t need a power supply to retain the data. |
| 3 | It is temporary data storage. | It is permanent data storage. |
| 4 | It stores data at low speed. | It stores data at high speed. |
| 5 | There size are not much larger and goes upto GBs. | There size are much larger than memory and goes upto TBs. |
| 6 | It is used when data is stored for short time. | It is used when data is stored for long term. |
| 7 | It is portable easily. | It is not portable easily. |
| 8 | It stores data on a memory stick in the form of electric formats. | It stores data on a hard disk in the form of magnetic memory. |
| 9 | It is not costly as compared to hard disk. | It is costly. |
| 10 | It retrieves data at relatively low speed. | It retrieves data at high speed. |