USB data recovery refers to the retrieval of files and information originally stored on and somehow deleted from digital storage devices which connect to your computer by means of the USB port. Examples of USB digital storage devices are compact flash drives, camera memory cards, SD cards and external hard drives. All of these differ greatly in design but are exactly similar when attempting recovery of lost or damaged files. The primary difference when attempting file recovery on USB drive devices is that certain types of these such as external book drives are much larger in size and therefore require a program capable of scanning the stored memory at a higher speed. When attempting to use older file recovery programs on large hard drives of any kind, the time required for a complete and thorough scan can stretch up to a full week. Obviously, no one has the time available or would care to wait hundreds of hours for a hard drive scan to be completed. A quality program to recover deleted files should scan and recover an entire hard drive in from one to four hours. Because many USB drive devices such as flash drives are considerably smaller, ranging from 1 to 16 GB these can be scanned and have files recovered from them in just a few minutes.