Information Technology - Module 5

IDE (Integrated Drive Electronics)

A hard drive whose disk controller is integrated into the drive, eliminating the need for a controller cable and thus increasing speed as well as reducing price.

AHCI (Advanced Host Controller Interface)

A technical standard that improves the performance of a computer's storage devices and operating system by optimizing data transfer. Uses the SATA interface. 

NVMe (Non-Volatile Memory Express)

An interface standard used to connect an SSD to the system and that uses the PCI Express ×4 interface to communicate with the processor; about five times faster than SATA Revision 3.x.

Parallel Advanced Technology Attachment (PATA)

A standard interface that connects storage devices to older computer systems.

Serial Advanced Technology Attachment (SATA)

A standard interface for connecting storage devices like hard disk drives (HDDs), solid-state drives (SSDs), and optical drives.

M.2 Form Factor

A type of solid-state drive (SSD) that's small and thin, similar in shape to a stick of gum and formerly known as the Next Generation Form Factor, is a specification for internally mounted computer expansion cards and associated connectors.

Magnetic Hard Drive

One of two technologies used by hard drives where data is stored as magnetic spots on disks that rotate at a high speed.

Read/Write Head

A sealed, magnetic coil device that moves across the surface of a disk in a hard disk drive (HDD), either reading data from or writing data to the disk.

Solid State Drive (SSD)

An electronic storage device with no moving parts that uses memory chips to store data instead of spinning disks (such as those used by magnetic hard drives and optical drives).

NAND Flash Memory

The type of memory used in SSDs. NAND stands for “Not AND” and refers to the logic used when storing a 1 or 0 in the grid of rows and columns on the memory chip.

AND

A logical operator that compares two values and returns true if both values are true. 

Throughput

A measurement of the amount of data that flows through a point in the data path over one second’s time. Usually measured in MB/sec.

Input/Output Operators per Second (IOPS)

A measurement of read or write operations performed in one second.

Latency

Delays in network transmissions that result in slower network performance; measured by the round-trip time it takes for a data packet to travel from source to destination and back to the source.

Low-Level Formatting

A process (usually performed at the factory) that electronically creates the hard drive tracks and sectors and tests for bad spots on the disk surface.

Wear Leveling

A technique used on a solid-state drive that ensures the logical block addressing does not always address the same physical blocks; this technique distributes write operations more evenly across the device. 

Small Computer System Interface (SCSI)

An interface between a host adapter and the CPU that can daisychain as many as 7 or 15 devices on a single bus.

Hot-Swapping

Plugging in a device while the computer is turned on. The computer will sense the device and configure it without rebooting. In addition, the device can be unplugged without an OS error.

SATA Express

An interface standard that uses a unique SATA connector and combines PCIe and SATA to improve the performance of SATA Revision 3.x; three times faster than SATA Revision 3.x but not as fast as NVMe.

Non-Volatile Memory Express (NVMe)

An interface standard used to connect an SSD to the system and that uses the PCI Express ×4 interface to communicate with the processor; about five times faster than SATA Revision 3.x.

Redundant Array of Independent Disks (RAID)

Several methods of configuring multiple hard drives to store data to increase logical volume size and improve performance or to ensure that if one hard drive fails, the data is still available from another hard drive.

Fault Tolerance

The degree to which a system can tolerate failures. Adding redundant components, such as disk mirroring or disk duplexing, is a way to build fault tolerance. 

Spanning

A configuration of two hard drives that hold a single Windows volume to increase the size of the volume.

Striped Volume

The term used by Windows for RAID 0, a type of dynamic volume used for two or more hard drives; writes to the disks evenly rather than filling up allotted space on one and then moving on to the next.

Mirrored Volume

The term used by Windows for the RAID 1 level that duplicates data on one drive to another drive and is used for fault tolerance.

RAID 0

Using space from two or more physical disks to increase the disk space available for a single volume. Performance improves because data is written evenly across all disks. Windows calls RAID 0 a striped volume.

RAID 1

A type of drive imaging that duplicates data on one drive to another drive and is used for fault tolerance. Windows calls RAID 1 a mirrored volume.

RAID 5

A technique that stripes data across three or more drives and uses parity checking, so that if one drive fails, the other drives can re-create the data stored on the failed drive. RAID 5 drives increase performance and provide fault tolerance.

RAID 5 Volumes

The term used by Windows for RAID 5

RAID (One-Zero) 10

A combination of RAID 1 and RAID 0 that requires at least four disks to work as an array of drives and provides the best redundancy and performance. 

Defrag and Optimization (dfrgui.exe)

A Windows utility that defragments a magnetic hard drive and trims an SSD to improve performance.

Disk Cloning (Windows)

Making an exact image of a hard drive, including partition information, boot sectors, operating system installation, and application software, to replicate the hard drive on another system or recover from a hard drive crash.

Chkdsk (Windows)

A Windows command to verify that the hard drive does not have bad sectors that can corrupt the file system. 

Boot Configuration Data (BCD)

A small Windows database that is structured the same as a registry file and that contains configuration information about how Windows is started. The file is stored in the \Boot directory of the hidden system partition. 

Bootrec (Windows)

A Windows command used to repair the BCD and boot sectors. 

Diskpart (Windows)

A Windows command to manage hard drives, partitions, and volumes. 

File System

The overall structure that an OS uses to name, store, and organize files on a disk. 

Volume

A primary partition that has been assigned a drive letter and can be formatted with a file system such as NTFS.

Formatting

The Windows command to prepare a hard drive volume, logical drive, or USB flash drive for use (e.g., format d:). This process erases all data on the device. 

Compact Disc File System (CDFS)

The 32-bit file system for CD discs and some CD-R and CD-RW discs

Universal Disk Format (UDF)

A file system for optical media used by all DVDs and some CD-Rs and CD-RWs. 

Compact Disc (CD)

An optical disc technology that uses a red laser beam and can hold up to 700 MB of data. 

Digital Video Discs (DVD)

A technology for optical discs that uses a red laser beam and can hold up to 17 GB of data. 

Blue-ray Discs (BD)

An optical disc technology that uses the UDF version 2.5 file system and a blue laser beam, which is shorter than any red beam used on DVDs or CDs. The shorter blue laser beam allows Blu-ray discs to store more data than a DVD. 

Secure Digital (SD) Cards

A group of standards and flash memory storage cards that come in a variety of physical sizes, capacities, and speeds. 

CompactFlash (CF) Cards

A flash memory device that allows for sizes up to 137 GB, although current sizes range up to 512 GB. 

XQD Cards

A flash memory device used in high-end cameras. Successor to CF cards; succeeded by CFexpress cards. 

CFexpress Cards

A flash memory device that allows for faster data transfer because they are designed using the PCIe 3.0 interface standard; CFexpress; comes in three form factors: A, B, and C.