Standard Drives (IDE/PATA/EIDE) – ATA transfers data between the hard disk and system using 16 bits with speeds of up to 100 MB/133MB per second. Uses Programmed Input Output (PIO) or Ultra direct Memory Access (UDMA) technology to transfer data. Maximum 4 HDDs can be connected
Serial Attachment (SATA) – Transfers data using 1 bit with the speed of 600MB per second. Uses a smaller 7 wire cable to connect to the system. You can connect one SATA drive to a SATA controller on motherboard and there is no master/slave concept
Small Computer Systems Interface (SCSI) Hard Disk Drives – High-speed interface that enables you to connect up to 15 devices on a single port
External Hard Disk Drives – Connected using USB2 and Firewire Interfaces
Wireless HDD – Requires external power supply. DTR is 54 Mbps, supports wireless 802.g standard and provides interface RJ45 and USB 1.1
ATA – 1 – uses 8 bit or 16 bit interface and has a transfer rate up to 8.3 MBps. Supports PIO mode 0,1 and 2 and it is obsolete
ATA – 2 – also known as EIDE. Uses PIO mode 3 and 4 has a transfer rate 16.6 MBps. Supports drives up to 8.4 GB and it is obsolete
ATA – 3 – Supports S.M.A.R.T feature
ATA – 4 – uses UDMA/33 and DTR is 33MBps. Also called as Advanced Technology Attachment Packet Interface (ATAPI)
ATA – 5 – uses UDMA/66 with 16 bit data width and 40/80 pin cable
ATA – 6 – Uses UDMA/100 with 16 bit data width and 40/80 pin cable
ATA – 7 – uses DTR up to 133 MBps and requires 80-conductor cable
Capacity & Cost – With advance technology cost of the HDD gradually decreased and the capacity of the hard disk also increased
Performance – Depends on the way the data is stored and retrieved on HDD
Reliability – Measured in terms that user should be able to retrieve and store data when required
RPM – RPM is the count of the revolutions made by the hard disk per minute
Platters – Round disks that are made up of metal or glass. Glass platters are preferred as shape of glass does not change when hard disk heats up
Recording Media – Made up of a magnetic material such as iron oxide and data is stored in this layer
Read / Write Head – Used to read and write the data on the hard disk. While the disk is reading or writing data to the disk the head does not touch the disk
Head Actuator Mechanism – Moves the read/write head from center of the platter to the edge of the platter
Air Filters – Cleans the air circulating in the hard disk
Hard Disk Temperature Acclimation – Time that hard disk must not be used after it is transported from a place having cold climate to a place having warm climate. Air vents in hard disk that are used for equalizing pressure in hard disk
Spindle Motor – Spins the hard disk platters. They have to spin for many continuous hours without causing a lot of vibrations
Logic Board – Controls the hard disk and stores data on hard disk platters
Cables and Connectors – Attached to the back of the hard disk
Configuration Items – Sets the hard disk using jumpers
Faceplate – Front plastic covering of the hard disk. Latest hard disks do not have a bezel
File system determines the way files and folders are stored on hard disk
File Allocation Table (FAT) – Stores the piece of file data known as clusters on the hard disks
New Technology File System (NTFS) – Offers high level of security for the stored files. File does not get corrupted when it is saved due to any physical or technical problems such as power failure
Extended File system (EXT) – Has a root directory and all the files and folders are stored in root directory. Has a feature called Journaling that keeps a log file with data
Used to create multiple logical drives or partitions
Makes your system start faster and it also enables you to install multiple operating systems on the different partitions
Fdisk utility enables you to divide the hard disk into multiple partitions
You can partition a hard disk
while installing operating system or using a utility such as Fdisk or partition magic
Three types:
