Hard drive is a data storage device used for saving and retrieving digital information. It general, it uses one or more rapidly rotating platters which are coated with magnetic material to store the data. The platters contain magnetic heads which are arranged in a way so they can move to read and write the information from the platter surfaces. From these hard drive data can be retrieved in random manner, it means data can be stored or regained in any order rather than consecutively. These hard drives are none volatile, which means the data remain stored in there even when powered off.
These hard devices are used to store and retrieve information permanently. There are various hard drive sizes are available. Generally 3.5 size drives are used for desktops and 2.5 for laptop computers. A hard drive can have multiple disks inside it. These disks connected to the motherboard with the help of an ATA (Advanced Technology Attachment), SCSI (Small Computer System Interface), SAS (Serial attached SCSI) or SATA (Serial Advanced Technology Attachment) cable. It requires only five volt power supply which comes from PSU (power supply unit). There are various types of hard drives are available in market. These hard drives have different advanced features and high data storage capacity.
All most desktop hard drive plates spin at a 7200 rpm rate. Only few high performance drives are available with a 10000 rpm spin rate. Mostly, all the hard drive producers and computer measure the capacity of hard disk in TB (terabytes) or GB (gigabytes). After formatting the hard drive, the storage capacity of its actually less compare to the original drive space.
RAID (Redundant Array of Inexpensive Disks) is something that has existed in the computer world. RAID is way of using multiple hard drives together in order to improve the performance and data reliability. There are various RAID types are available such as 0, 1, 5, 0+1, 1+0 or 10. Each of these has exact requirements for hardware and has various benefits and drawbacks.
Solid State Drives is also known as SSD. It is the advanced data storage drive. It is used in the replace the hard disk drives because of its advanced performance over HDD. It contains many advanced features compared to hard disk such as faster access times, lower latency and also does not contain any physical movement part compared to hard disk. It is becoming more and more popular.