A Hard Disk Drive (HDD) is used by a computer to store data. Unlike RAM, the data stored on it will not be deleted after the computer is shut down. The main components include two electric motors which spin as an arm reads and writes data over the disk.
Types of Hard Drives- Parallel ATA (PATA) – Older types of hard drives, used to be called Enhanced Integrated Drive Electronics (EIDE) drives. Some models are still sold.
- Serial ATA (SATA) – The most common type of hard drive in most modern computers. Can transfer files faster than PATA drives.
- Small Computer Simplified Interface (SCSI) – These drives are more powerful than both PATA and SATA drives, and also much more expensive.
- Puchasing When buying a hard drive the most important aspect is obviously its size. 250 GB is the standard on most modern computers, and it's probably fine for people who don't plan on storing lots of music or videos. However, if you do plan to store large files it may be worth investing in a larger hard drive.