Data segment

In computing, a data segment (often denoted .data) is a portion of an object file or the corresponding virtual address space of a program that contains initialized static variables, that is, global variables and static local variables. The size of this segment is determined by the size of the values in the program's source code, and does not change at run time.

The data segment is read-write, since the values of variables can be altered at run time. This is in contrast to the read-only data segment (rodata segment or .rodata), which contains static constants rather than variables; it also contrasts to the code segment, also known as the text segment, which is read-only on many architectures. Uninitialized data, both variables and constants, is instead in the BSS segment.

Historically, to be able to support memory address spaces larger than the native size of the internal address register would allow, early CPUs implemented a system of segmentation whereby they would store a small set of indexes to use as offsets to certain areas. The Intel 8086 family of CPUs provided four segments: the code segment, the data segment, the stack segment and the extra segment. Each segment was placed at a specific location in memory by the software being executed and all instructions that operated on the data within those segments were performed relative to the start of that segment. This allowed a 16-bit address register, which would normally provide 64KiB (65536 bytes) of memory space, to access a 1MiB (1048576 bytes) address space.

Data (disambiguation)

Data is uninterpreted information.

Data or DATA may also refer to:

Music

DATA (band)

DATA were an electronic music band created in the late 1970s by Georg Kajanus, creator of such bands as Eclection, Sailor and Noir (with Tim Dry of the robotic/music duo Tik and Tok). After the break-up of Sailor in the late 1970s, Kajanus decided to experiment with electronic music and formed DATA, together with vocalists Francesca ("Frankie") and Phillipa ("Phil") Boulter, daughters of British singer John Boulter.

The classically orientated title track of DATA’s first album, Opera Electronica, was used as the theme music to the short film, Towers of Babel (1981), which was directed by Jonathan Lewis and starred Anna Quayle and Ken Campbell. Towers of Babel was nominated for a BAFTA award in 1982 and won the Silver Hugo Award for Best Short Film at the Chicago International Film Festival of the same year.

DATA released two more albums, the experimental 2-Time (1983) and the Country & Western-inspired electronica album Elegant Machinery (1985). The title of the last album was the inspiration for the name of Swedish pop synth group, elegant MACHINERY, formerly known as Pole Position.