A byte is a series of bits of a particular length, usually 8. Computer storage space is measured in bytes.
A Kilobyte (or 1 K) represents 1024 bytes and a Megabyte (1 Mb) represents one thousand “K” bytes, or one million bytes.
While a bit can only represent 2 values (0 or 1), a byte can represent 256 distinct values (28). This means that each byte, is able to represent one of 256 characters or operations. Grouping data into bytes in such a way improves storage efficiency and makes it easier for humans to comprehend and debug. Without this grouping, reading computer language would be a lot like reading Tolstoy without any spaces between words.
Also See: Bit
Frequently Asked Questions
Does Mb mean the same thing in Mbps?
Mbps, which you will often see associated with the speed of your Internet connection or wireless adapter, actually stands for megabits per second. A megabit is a million bits, whereas a megabyte is a million bytes. Remember that a byte is a collection of 8 bits, so that megabit your ISP is referring to is 1/8 the size of a megabyte. If your broadband speed is 30 Mbps, don’t expect to download a 30-megabyte song in 1 second…it will take at least 8 seconds.
Bits are used to refer to transfer speeds, because most transfer protocols process information at the level of individual bits; whereas storage is referred to in terms of bytes, because information is grouped into bytes on your hard drive. To make matters more confusing, while Mbps always refers to megabits per second, Mb can refer to megabits or megabytes, depending on the context.
Are bits always grouped in series of 8?
Not always. In fact, most modern machines now use 32- or 64-bit processing. However, most storage systems are still based on the IBM design from the mid-eighties. Early computers grouped information in smaller clumps, due to technological limitations; however, doing so resulted in far fewer options for each set. For example, a set of 4 bits only gives you 16 possible characters, which barely gets you halfway through the English alphabet…and only if you skip lowercase letters altogether. The 8-bit grouping is more than large enough to include every letter, number, and special character, while still having plenty of space left over. While computers are capable of handling far more bits at once, the 8-bit system has remained the standard largely because it still works and it’s easy for humans to follow.
Can you have a different size byte?
Yes. Bytes have varied in size, but as mentioned above, 8-bits have been the standard for several decades, because of their size and ease for humans. There have been attempts at 7-bit and 9-bit bytes, but these largely failed because odd numbers are not as easy to break apart. Any less than 7-bits is generally not useful, as it can’t even fit all the options on a keyboard. And anything more than 9-bits is harder for humans to comprehend.