GLOSSARY

• Clicks, Clicking – A sound when made in regular intervals by a drive indicates that there are mechanical problems with the drive. Data should be backed up ASAP, if possible. Also known as "click of death".

• Drive Enclosure – A case made of plastic or metal that houses one or more hard drives to connect externally to a computer. Common connectors are USB, FireWire 400/800, or eSATA. Might need a separate power supply.

• eSATA – Variant of the SATA connector to connect drives externally.

• File System – In order to store data on a drive it needs to be formatted with a file system that the OS understands. Generally speaking, for Windows that is typically NTFS or FAT32, for Macs HFS+, and for Linux currently ext3. Macs and Linux can read and write the Windows file systems as well (additional software may be required).

• FireWire (IEEE 1394) – An interface to connect external peripherals to a computer, similar to USB. Comes in two variants, FireWire 400 and FireWire 800, which are compatible with the appropriate cables.

• Firmware – Software stored in the System Area with detailed information regarding the specific model and configuration. Not readable through ordinary means.

• Head Crash – When one or more of the read/write heads no longer float on an air cushion over the rotating disks, but actually touch the disk surface. This causes severe damage, and a drive having experienced head crashes cannot be repaired without special tools in a clean room.

• IDE (also EIDE or PATA) – An interface used to connect drives internally that has been widely replaced by SATA.

• OS – Operating System, describes software loaded from disk that allows the user to work with the computer.

• Platter – One or more magnetic disks rotating within the drive, containing magnetically stored bits of information. Most drives contain more than one platter, and one or both sides can be used for data storage.

• Perpendicular Recording – Technique used on newer drives to store more information per square inch by orienting the data perpendicular to the platter surface.

• Printed Circuit Board (PCB) – Typically a green board that carries the necessary electronics of a drive and can be found on the bottom of a bare drive. Prone to damage from electrostatic discharges; direct contact with hands etc. should be avoided.

• SATA – The current standard to connect drives internally with a transfer rate of up to 3Gb/s.

• SCSI – Stands for Small System Computer Interface. An interface to connect drives and other peripherals either internally or externally, but no longer in use. Replaced by USB and FireWire for external devices, or SATA for internal connections.

• System Area – Special area on the drive with detailed information that is model specific like firmware and platter/head configuration. Not accessible through ordinary means.

• USB – Universal Serial Bus. A connector that allows to attach various external devices to a computer, including external hard drives.