Disk Operating System/Units of Information
Objective[edit | edit source]
Units of Information[edit | edit source]
Computer Memory[edit | edit source]
When working with a x86 computer, you'll need to know how to measure the size of memory. The difference between a byte and a word is very important to know, since you'll need that knowledge when working with a file system for example. This lesson will help you get familar with the units of information used on the x86 computer.
The Bit[edit | edit source]
The bit is a unit of size that can store two values, one and zero. When working with computers, data is usually stored in binary, a number system that is 2 based. A bit is basicly like a standard light switch. It's only possible values are on and off, much like a bit's one and zero values. This unit of size is important to remember when working with computers, since it is as low as you get in terms of memory size.
Nibble[edit | edit source]
The nibble (or sometimes spelled nybble to match the spelling of byte) is the size of four bits. The nibble is half the size of a byte. In telecommunications and networking, a nibble is referred to as semioctet or a quartet.
Byte[edit | edit source]
The byte is the size of eight bits. In telecommunications and networking, a byte is referred to as an octet. On rare occasions, a byte is sometimes called a halfword.
Word[edit | edit source]
The word is one of the most ambiguous units of information in computer science. On the x86 architecture, a word is the size of sixteen bits.
Dword[edit | edit source]
The Dword stands for doubleword. On the x86 architecture, a Dword is the size of thirty-two bits.
Qword[edit | edit source]
The Dword stands for quadword. On the x86 architecture, a Qword is the size of sixty-four bits.
Metric System[edit | edit source]
In addition to the sizes mentioned above, you can append a metric prefix to the unit byte or bit and create a large number in terms of bytes or bits. For example you could take the metric prefix kilo- and append it to byte and you create kilobyte, which stands for 1,000 bytes. You could also appended the metric prefix mega- to bit and create megabit. There is a table of common metric bytes and bits listed below. You probably won't need to remember anything larger than that, but who knows what the future holds.
IEC Standards[edit | edit source]
Units of Conflict[edit | edit source]
Assignments[edit | edit source]