| Compact Flash card (CF) is a type of a | | | | being non-volatile and solid state, can |
| data storage device, especially useful | | | | be electrically erased and rewritten. |
| for portable electronic devices. It can | | | | Flash memory allows multiple memory |
| be used directly in a CF card slot with | | | | locations to be erased or written in one |
| an adapter. It makes use of flash | | | | programming operation. It can thus |
| memory. Based on physical features, | | | | operate at much higher read-access |
| there are two types of Flashcards: Type | | | | speeds. Better shock resistance than |
| I (3.3mm thick) and the thicker Type II | | | | hard disks is another of its useful |
| (CF2) cards (5mm thick). | | | | feature. Features as these make these |
| First produced by SanDisk in 1994, | | | | cards much more preferable over the |
| Compact Flash card is among the first | | | | others such as battery-powered devices. |
| and the oldest and also the most | | | | A limitation of this card is that being |
| successful brands and is now used for a | | | | easily rewritable memory, it can be |
| variety of devices which includes | | | | overwritten without warning leading to |
| laptops, portable audio recorders and | | | | loss of data. System failure, power |
| desktop computers and cameras. | | | | fluctuations, corruption caused by |
| Flash memory devices consume very less | | | | hardware crash or software malfunctions |
| power and yet have good transfer speeds. | | | | are the other limitations. |
| They can also be switched from one | | | | Flash memory stores one bit of |
| system to another. They are also | | | | information in an array of transistors, |
| designed to adjust to very rapid changes | | | | called 'cells'. Compact Flash Cards are |
| in temperature or in voltage. The | | | | built on the basis of the type of logic |
| storage capacity of a Compact Flash card | | | | gate used in each storage cell and are |
| ranges from 128 MB to about 64 GB. | | | | thus of two types: NOR flash and NAND |
| However, 256 MB and 2 GB are the most | | | | flash. Recently however, some flash |
| popular choices in Europe. | | | | memory devices called multi-level cell |
| Flash memory has a specific quality | | | | devices, can store more than one bit per |
| which allows a section of its memory | | | | cell. NOR flash cell has two gates: the |
| cells to get erased in a single | | | | Control Gate and the Floating Gate. NAND |
| 'flash', very much reminiscent of a | | | | Flash has a different mechanism: tunnel |
| camera flash function. This reminds one | | | | injection for writing and tunnel release |
| of the ease with which erasure of data | | | | for erasing. |
| can be carried out, freeing space for | | | | The market demand today is tilting |
| recording new data onto it. Flash memory | | | | towards the lower-priced NAND flash. |