- Hard Drives
- Floppy Drives
- CD-ROM
- CD-R
- CD-RW
- DVD-ROM
- DVD-R
- DVD+R
- DVD-RW
- Blue Ray
- Removable Drives
HARD DRIVES
These are also called 'fixed disks' in ancient computerese because the storage media is mounted within the computer and not intended to be removed.
Hard drives consist of one or more metal platters stacked together on a single spindle. Multiple read/write heads (one for the top and bottom of each platter) float next to the surface of the drive. Hard Disk drive capacities are determined by the number of cylinders and blocks per cylinder a drive will support.
FLOPPY DRIVES
Named for the media disks that could be pulled out and that would 'flop' when carried. These disks are designed to allow users to store data to a disk, remove it and carry the data elsewhere. These typically come in one of two formats in the United States: 3.5" @1.44Mbytes and 5.25" at 1.22 Mbytes. There are a few proprietary types as well, such as Zip drives, DAT tapes etc.
CD-ROM
Compact Disk Read Only Memory or CD-ROMs are shiny circular pieces of plastic with a hole in the middle. These look like audio compact disks and computer software and data are stored on them. They are read using a powerful (red) light-emitting diode (LED) that is sometimes called a 'laser' and thus the name 'laser disk'. Compact Disk media is made of pressed layers of plastic and can store about 640 MB of data.
DVD-ROM
Digital Video Disks were first used to store movies for playback on compact players.
Blu-Ray
The latest development in data storage and movie disks is Blu-Ray, so called because it uses a blue LED (sometimes called a laser, which is actually something entirely different) to read/write from the disk.
REMOVEABLE DRIVES
These are drives where the drive itself can be removed or ported elsewhere. The media is usually not pulled out. Removable hard drives are a good example of these.
DISK DRIVE CAPACITIES
| DRIVE TYPE | ACCESS METHOD | CAPACITY | ||
| Floppy Drive (3.5") | Rewriteable | Magnetic Media | 1.44 MB | |
| Hard Drive | Rewriteable | Magnetic Media | Various | |
| Zip Drive | Rewriteable | Magnetic Media | Various | |
| CD-ROM | Compact Disk | Read-Only | Optical Media | ~640 MB |
| CD-R | CD Recordable | Write Once | Optical Media | ~640 MB |
| CD-RW | CD Rewriteable | Rewriteable | Optical Media | ~640 MB |
| DVD | Digital Video Disk | Read-Only | Optical Media | ~4.7 GB |
DVD-R/DVD+R |
DVD Recordable | Write Once | Optical Media | ~4.7 GB |
| DVD-RW | DVD Rewriteable | Rewriteable | Optical Media | ~4.7 GB |
DVD-R/DVD+R DL |
DVD Recordable Dual Layer | Write Once | Optical Media | ~4.7 GB |
| DVD-RW DL | DVD Dual Layer | Rewriteable | Optical Media | ~8.5 GB |
| BD-ROM | Blu-ray | Read-Only | Optical Media | 25 GB |
| BD-R | Blu-ray | Write Once | Optical Media | 25 GB |
| BD-RE | Blu-ray | Rewriteable | Optical Media | 25 GB |
| BD-R (DL) | Blu-ray Dual Layer | Write Once | Optical Media | 50 GB |
| BD-RE (DL) | Blu-ray Dual Layer | Rewriteable | Optical Media | 50 GB |