LXE 1280, Reference Manual

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File Structure 19
E-SW-LDSPLUSRG-G LDS Plus Reference Guide
Memory, Disk Drives and File Storage
Computer memory and disk drive activity are performed by operating system functions and
special file commands.
Terminology
Software is the set of programs, procedures, and related on-line documentation associated with a
computer system. A program is a coded set of instructions that interprets the information you give
to the computer with the keyboard or a mouse, and then directs your computer to carry out a task.
Memory is the area where the computer stores data. Memory contents can be permanent and
inalterable (ROM) or temporary (RAM or Flash). Conventional memory is the first 640Kb where
the operating system runs programs and stores data. It is also called base memory.
DOS is an acronym for Disk Operating System. Several brands of DOS have been created by
various companies, but in all cases, DOS - whether ROM-DOS, MS-DOS, or X-DOS - is a set of
commands or codes which tells the computer how to process information.
A file is a defined set of related information which is electronically stored for use by your
computer. A file may be stored on a diskette (also called a floppy), on a hard drive, on a PC card,
or a file may reside in computer memory (RAM or ROM).
Computer information is stored in bytes regardless of where it resides. A byte can be thought of as
the amount of space it takes to store one character. Amounts of computer memory are often
measured in the following terms:
•
Kb stands for kilobyte. Although one kilobyte is thought of as one thousand bytes, it
is actually 1,024 bytes in computer memory.
•
MB stands for megabyte. Although one megabyte is thought of as one million bytes;
the real number is 1,048,576 bytes.