Boot Sector

A boot sector or boot block is a region of a hard disk, floppy disk, optical disc, or other data storage device that contains machine code to be loaded into random-access memory (RAM) by a computer system's built-in firmware. The purpose of a boot sector is to allow the boot process of a computer to load a program (usually, but not necessarily, an operating system) stored on the same storage device. The location and size of the boot sector (perhaps corresponding to a logical disk sector) is specified by the design of the computing platform.

On an IBM PC compatible machine, the BIOS selects a boot device, then copies the first sector from the device (which may be a MBR, VBR or any executable code), into physical memory at memory address 0x7C00. On other systems, the process may be quite different.

Read more about Boot Sector:  Kinds of Boot Sectors, Operation, Boot Sector Viruses

Other articles related to "boot, sector, boot sector, sectors, boot sectors":

Stoned (computer Virus) - Original Version
... On hard disks, the original master boot record is moved to cylinder 0, head 0, sector 7 ... On floppy disks, the original boot sector is moved to cylinder 0, head 1, sector 3 ... Cylinder 0, head 1, sector 3 is the last directory sector on 360 Kb disks, and the author believed that it was "safe" to overwrite ...
... It will therefore install a boot sector capable of booting the operating system into the first logical sector of the volume ... Due to restrictions in the implementation of the boot loaders in the boot sector and DOS' IO system, these two files must reside in the first two directory entries and be stored at the beginning of the data ... Depending on version, the whole files or only a varying number of sectors of the DOS-BIOS (down to only three sectors in modern issues of DOS) will have to be stored in one consecutive part ...
DOS - Design - Boot Sequence
... The bootstrap loader on PC-compatible computers (MBR or boot sector) is located at track zero, the first sector on a disk ... The ROM BIOS will load this sector into memory at address 0000h7C00h, and typically check for a signature "55h AAh" at offset +1FEh ... If the sector is not considered to be valid, the ROM BIOS will try the next physical disk in the row, otherwise it will jump to the load address with certain registers set up ...
Chain Loading in Boot Manager Programs
... In operating system boot manager programs, chain loading is used to pass control from the boot manager to a boot sector ... The target boot sector is loaded in from disk, replacing the in-memory boot sector from which the boot manager itself was bootstrapped, and executed ...
Boot Sector Viruses
... Since code in the boot sector is executed automatically, boot sectors have historically been a common attack vector for computer viruses ... behavior, the BIOS often includes an option to prevent writing to the boot sectors of attached hard drives ...

Famous quotes containing the word boot:

    ... until the shopkeeper plants his boot in our eyes,
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    or how we knelt at the yellow bulb with sighs
    like moth wings for a short while in a small place.
    Anne Sexton (1928–1974)