Chapter 4 Flashcards
8.3 filename
A filename that consists of no more than eight characters plus an optional dot (.) and three-character extension. This file-naming limit exists in DOS and the original File Allocation Table (FAT) filesystem it uses.
ATA
A popular 16-bit interface standard that extends the ISA bus of the IBM PC-AT to attach peripherals; it has evolved through over 5 generations; the original ATA is better known as IDE.
BIOS
A simple, low-level operating system which supplies a uniform API to higher-level operating systems; BIOS is generally implemented in ROM of some sort.
Boot
To cause the operating system to begin to function. Takes its name from “pulling oneself up by the bootstraps”, a whimsical analogy applied to the BIOS loading itself and then running the “boot loader”.
CHS geometry
A method of hard disk addressing in which a triplet of numbers (a cylinder, a head, and a sector) is used to identify a specific sector. CHS geometry addressing contrasts with logical block addressing (LBA).
Compression
Removal of redundant information from a file or data stream, to reduce its size, the storage space it needs, or the time needed for transmission. Lossy compression actually discards information that is considered not essential, and is only appropriate for data like images or sound.
CPU
The main component that makes a computer work; these days usually a “micro-processor” on a single silicon chip. (See processor.)
CYlinder/head/sector (CHS) geometry
A method of hard disk addressing in which a triplet of numbers (a cylinder, a head, and a sector) is used to identify a specific sector. CHS geometry addressing contrasts with logical block addressing (LBA).
D-Bus
The Desktop Bus (D-Bus) provides a further abstraction of hardware information access. Like hald, D-Bus runs as a daemon. D-Bus enables processes to communicate with each other as well as to register to be notified of events, both by other processes and by hardware (such as the availability of a new USB device).
Direct memory addressing (DMA)
A means of transferring data between devices (such as sound cards or SCSI host adapters) and memory without directly involving the CPU.
DMA
A means of transferring data between devices (such as sound cards or SCSI host adapters) and memory without directly involving the CPU.
DMA Addresses
Direct memory addressing (DMA) is an alternative method of communication to I/O ports. Rather than have the CPU mediate the transfer of data between a device and memory, DMA permits the device to transfer data directly, without the CPU’s attention. The result can be lower CPU requirements for I/O activity, which can improve overall system performance.
EEPROM
Electronically erasable programmable read-only memory (EEPROM)
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A type of data storage chip that retains data when power has been turned off but that can be erased and rewritten electronically. Frequently used to store a computer’s or plug-in card’s firmware.
Electronically erasable programmable read-only memory
A type of data storage chip that retains data when power has been turned off but that can be erased and rewritten electronically. Frequently used to store a computer’s or plug-in card’s firmware.
Enhanced Host Controller Interface (EHCI)
A type of controller for USB 2.0 ports.
ext2
The most common filesystem (meaning 1) in Linux from the mid-1990s through approximately 2001.
Ext2fs
The most common native Linux filesystem (meaning 1) from the mid-1990s through approximately 2001.
ext3
A variant of the Second Extended Filesystem (ext2 or ext2fs) that adds a journal to reduce startup times after a power failure or system crash. See also journaling filesystem.
ext3fs
A variant of the Second Extended Filesystem (ext2 or ext2fs) that adds a journal to reduce startup times after a power failure or system crash. See also journaling filesystem.
ext4
The fourth version of the popular Linux filesystem. Ext4fs adds the ability to handle larger files and filesystems, as well as various performance enhancements, to the ext3fs feature set.
ext4fs
The fourth version of the popular Linux filesystem. Ext4fs adds the ability to handle larger files and filesystems, as well as various performance enhancements, to the ext3fs feature set.
Extended Partition
A type of disk partition in the MBR partitioning scheme. Extended partitions are placeholders for one or more logical partitions.
Extents File System (XFS)
One of several journaling filesystems for Linux. XFS was developed by Silicon Graphics (SGI) for its IRIX OS and then ported to Linux.
Filesystem
Filesystem
The low-level data structures recorded on a disk in order to direct the placement of file data. The filesystem determines characteristics like the maximum file size, the file-naming rules, and what extra data (time stamps, ownership, and so on) may be associated with a file.
The overall layout of files and directories on a computer. For instance, a Linux filesystem includes a root directory (/), several directories under this (/usr, /var, /boot, and others), subdirectories of these, and so on.
Floppy Disk
A magnetic storage medium with a flexible disk inside; See Hard disk.
Fourth Extended File System (ext4fs or ext4)
The fourth version of the popular Linux filesystem. Ext4fs adds the ability to handle larger files and filesystems, as well as various performance enhancements, to the ext3fs feature set.
GPT
A partition table type that’s intended to replace the older MBR system. GPT is defined as part of the EFI specification but can also be used on BIOS-based computers.
GUID
Item 28 of 92 Grade This Item Correct Alt C and Incorrect Alt I
Globally unique identifier (GUID)
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A 128-bit number, defined and expressed in a specific manner. When properly constructed, the odds of two programs, or two runs of the same program, generating identical GUIDs are extremely small.
GUID Partition Table (GPT)
A partition table type that’s intended to replace the older MBR system. GPT is defined as part of the EFI specification but can also be used on BIOS-based computers.
HAL Daemon
The Hardware Abstraction Layer (HAL) Daemon, or hald, is a user-space program that runs at all times (that is, as a daemon) that provides other user-space programs with information about available hardware.
Hard disk
A computer device that uses solid disks as magnetic medium to store data. See Floppy disk.
HFS
A filesystem used on Mac OS.
Hierarchical File System (HFS)
A filesystem used on Mac OS.
High-level formatting
A type of disk formatting that writes the data that define a filesystem. Also called making a filesystem. See also low-level formatting.
I/O addresses
I/O addresses (also referred to as I/O ports) are unique locations in memory that are reserved for communications between the CPU and specific physical hardware devices.
Industry Standard Architecture (ISA)
The expansion bus used on the original IBM PC. Most manufacturers began dropping ISA from their motherboards around 2001.