BIT AND BYTES

Bandwidth

Bandwidth refers to how much data you can send through a network or modem connection. It is usually measured in bits per second, or "bps." You can think of bandwidth as a highway with cars travelling on it. The highway is the network connection and the cars are the data. The wider the highway, the more cars can travel on it at one time. Therefore more cars can get to their destinations faster. The same principle applies to computer data -- the more bandwidth, the more information that can be transferred within a given amount of time.

Baud

Contrary to popular belief, baud is not a direct measurement of data transfer speed, but instead it measures how many electrical signals are sent per second. Baud is used to measure the rate of electrical signals, or "signaling elements," for modems, networks, serial cables, and other data transfer mediums.

Some people think that baud and bits per second are equal. For example, they'll say a 28,800 bps modem transmits at 28,800 baud, and act like they know everything. But the fact is, most modems transmit multiple bits of data per baud, so while the the two values are related, they are typically not equal. So the next time your friend says his 56K v.90 modem can transfer data at 56,000 baud, you can kindly tell him that he is incorrect and explain to him the difference between baud and bps
Bit

The computer term "bit" comes from the phrase "Binary DigIT," which is different than that thing you put around a horse's mouth. A bit is a single digit number in base-2 (a zero or a one) and is the smallest unit of computer data. A full page of text is composed of about 16,000 bits.

It is important not to confuse bits with bytes. Both are used to measure amounts of data, but it takes eight bits to make one byte. The most common area where bits are used instead of bytes is in measuring bandwidth (in bits per second). Why? Probably because it makes your Internet connection sound faster than it really is.

Abbreviation: b

Bitrate

Bitrate, as the name implies, describes the rate at which bits are transferred from one location to another. In other words, it measures how much data is transmitted in a given amount of time. Bitrate is commonly measured in bits per second (bps), kilobits per second (Kbps), or megabits per second (Mbps). For example, a DSL connection may be able to download data at 768 kbps, while a Firewire 800 connection can transfer data up to 800 Mbps.

Bitrate can also describe the quality of an audio or video file. For example, an MP3 audio file that is compressed at 192 Kbps will have a greater dynamic range and may sound slightly more clear than the same audio file compressed at 128 Kbps. This is because more bits are used to represent the audio data for each second of playback. Similarly, a video file that is compressed at 3000 Kbps will look better than the same file compressed at 1000 Kbps. Just like the quality of an image is measured in resolution, the quality of an audio or video file is measured by the bitrate.

Blob (Binary Large Object)

If you're like me, you picture a blob as a enigmatic green object that lacks a defined shape or size. In the computer world, however, blobs are a bit easier to define. The term "blob" actually stands for "Binary Large Object" and is used for storing information in databases.

A blob is a data type that can store binary data. This is different than most other data types used in databases, such as integers, floating point numbers, characters, and strings, which store letters and numbers. Since blobs can store binary data, they can be used to store images or other multimedia files. For example, a photo album could be stored in a database using a blob data type for the images, and a string data type for the captions.

Because blobs are used to store objects such as images, audio files, and video clips, they often require significantly more space than other data types. The amount of data a blob can store varies depending on the database type, but some databases allow blob sizes of several gigabytes. Now that is a big blob!

bps

Stands for "Bits Per Second." (The "b" is lowercase because it stands for bits, not bytes.) Bits per second is the standard way of measuring how fast data moves across a network or phone system. For example, a 56K modem can hypothetically transfer data at 56,700 bits per second.
Byte

A byte is a set of 8 bits that represent a single character in the computer's memory. Do not confuse this term with "bite," as in taking a bite of a cookie, because that is totally different. While bits are often used to measure data transfer speeds, bytes are used to measure file sizes, hard disk space, and computer memory. Larger amounts of data are measured in units such as megabytes, gigabytes, and terabytes. For example, one kilobyte is equal to 1,024 bytes.

For a list of all the different units of measurements, view this Help Center article.

Data

Computer data is information processed or stored by a computer. This information may be in the form of text documents, images, audio clips, software programs, or other types of data. Computer data may be processed by the computer's CPU and is stored in files and folders on the computer's hard disk.

At its most rudimentary level, computer data is a bunch of ones and zeros, known as binary data. Because all computer data is in binary format, it can be created, processed, saved, and stored digitally. This allows data to be transferred from one computer to another using a network connection or various media devices. It also does not deteriorate over time or lose quality after being used multiple times.

Data Transfer Rate

The data transfer rate is commonly used to measure how fast data is transferred from one location to another. For example, a hard drive may have a maximum data transfer rate of 480 Mbps, while your ISP may offer an Internet connection with a maximum data transfer rate of only 1.5 Mbps.

Data transfer rates are typically measured in bits per second (bps) as opposed to bytes per second, which can be understandably confusing. Because there are eight bits in a byte, a sustained data transfer rate of 80 Mbps is only transferring 10MB per second. While this is confusing for consumers, Internet service providers must enjoy measuring data transfer rates in bps since it makes their Internet access speeds sound 8x faster than they really are.

Exabyte

An exabyte is 2 to the 60th power, or 1,152,921,504,606,846,976 bytes.

It can be estimated as 10 to the 18th power, or 1,000,000,000,000,000,000 bytes. An exabyte is 1,024 petabytes and precedes the zettabyte unit of measurement. While a 64-bit processor can theoretically use 16 exabytes of address space, exabytes are so large, the units are rarely used in a practical context. For example, it is estimated that all the printed material in the world only takes up about five exabytes.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: EB

A exbibyte is a unit of data storage that equals 2 to the 60th power, or 1,152,921,504,606,846,976 bytes.

While a exabyte can be estimated as 10^18 or 1,000,000,000,000,000,000 bytes, a exbibyte is exactly 1,152,921,504,606,846,976 bytes. This is to avoid the ambiguity associated with the size of exabytes. A exbibyte is 1,024 pebibytes and precedes the zebibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: EiB

Gibibyte

A gibibyte is a unit of data storage that equals 2 to the 30th power, or 1,073,741,824 bytes.

While a gigabyte can be estimated as 10^9 or 1,000,000,000 bytes, a gibibyte is defined as exactly 1,073,741,824 bytes. This helps avoid the ambiguity associated with the size of gigabytes. A gibibyte is 1,024 mebibytes and precedes the tebibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: GiB

Gigabyte

A gigabyte is 2 to the 30th power, or 1,073,741,824 bytes.

It can be estimated as 10 to the 9th power, or one billion (1,000,000,000) bytes. A gigabyte is 1,024 megabytes and precedes the terabyte unit of measurement. Hard drive sizes are typically measured in gigabytes, such as a 160GB or 250GB drive. The term gigabyte is often often abbreviated as simply a "gig" in speech. For example, if you have a 250GB hard drive, you could say, "I have 250 gigs of disk space." The prefix "giga" comes from the Greek word "gigas," meaning giant.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: GB
Kbps (Kilobits Per Second)

Stands for "Kilobits Per Second." Don't confuse this with Kilobytes per second (which is 8 times more data per second). This term is commonly used in describing data transfer rates. For example, two common modem speeds are 33.6 Kbps and 56 Kbps.
Kibibyte

A kibibyte is a unit of data storage that equals 2 to the 10th power, or 1,024 bytes.

While a kilobyte can be estimated as 10^3 or 1,000 bytes, a kibibyte is exactly 1,024 bytes. This is to avoid the ambiguity associated with the size of kilobytes. A kibibyte is 1,024 bytes and precedes the mebibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: KiB
Kilobyte

A kilobyte is 2 to the 10th power, or 1,024 bytes.

"But doesn't 'kilo' means one thousand?" you ask. Well yes, but in the computer world, certain rules and guidelines don't have the same influence they do in other areas of life. Just ask any computer programmer. A kilobyte is technically 1,024 bytes because it is measured by 2^10, which equals 1,024. However, kilobytes are often estimated as 10 to the 3rd power, or 1,000 bytes. While this makes it easier to add kilobytes together, estimating can throw off larger measurements. This is because 1,024 kilobytes equal one megabyte, 1,024 megabytes equal one gigabyte, and so on.

Most small files on your computer are measured in kilobytes. For example, thumbnail images might use only 5 to 10KB of space. A larger 900x600 pixel JPEG image can take up 250KB of space. Text files are often less than 1KB. Most documents you save on your computer should be between 1 and 1,024KB. Anything larger than 1,024KB is measured in megabytes.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: K or KB
Mbps (Megabits Per Second)

Stands for "Megabits Per Second." One megabit is equal to one million bits or 1,000 kilobits. While "megabit" sounds similar to "megabyte," a megabit is roughly one eighth the size of a megabyte (since there are eight bits in a byte). Mbps is used to measure data transfer speeds of high bandwidth connections, such as Ethernet and cable modems.
Mebibyte

A mebibyte is a unit of data storage that equals 2 to the 20th power, or 1,048,576 bytes.

While a megabyte can be estimated as 10^6 or 1,000,000 bytes, a mebibyte is exactly 1,048,576 bytes. This is to avoid the ambiguity associated with the size of megabytes. A mebibyte is 1,024 kibibytes and precedes the gibibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.
Abbreviation: MiB
Megabyte

A megabyte is 2 to the 20th power, or 1,048,576 bytes.

It can be estimated as 10 to the 6th power, or one million (1,000,000) bytes. A megabyte is 1,024 kilobytes and precedes the gigabyte unit of measurement. Large computer files are typically measured in megabytes. For example, a high-quality JPEG photo from a 6.3 megapixel digital camera takes up about 3MB of space. A four minute CD-quality audio clip takes up about 40MB of space and CDs can hold up to 700MB of space.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: MB
MTU (Maximum Transmission Unit)

Stands for "Maximum Transmission Unit." MTU is a networking term that defines the largest packet size that can be sent over a network connection. The MTU is typically limited by the type of connection, but may sometimes be adjusted in a computer's network settings. Because a higher MTU allows for more data to be transferred at once, connections with high MTUs typically have more bandwidth than connections with lower MTUs.

For example, the MTU of an Ethernet connection is 1500 bytes. If a system sends packets over an Ethernet network that are larger than 1500 bytes, the data will be fragmented into smaller packets. These packets will then need to be reassembled on the receiving computer. Fortunately, the receiving computer does this automatically. However, it may cause a slowdown in the overall data transfer. Since the majority of computers connected to the Internet go through an Ethernet connection at some point, most computers have a default MTU setting of 1500 bytes.
Null Character

A null character is a character with all its bits set to zero. Therefore, it has a numeric value of zero and can be used to represent the end of a string of characters, such as a word or phrase. This helps programmers determine the length of strings. In practical applications, such as database and spreadsheet programs, null characters are used as fillers for spaces.

Nybble

A nybble, sometimes spelled "nibble," is a set of four bits. Since there are eight bits in a byte, a nybble is half of one byte. While it may take the average person several nibbles to equal one bite of a cookie, in the computer world, two nybbles always equal one byte.

The four bits in a nibble allow it to have 16 possible values, which is the same as one hexadecimal digit. Therefore, a nybble is sometimes referred to as a "hex digit." In data communications, nybbles are sometimes called "quadbits," because of the four bits that make up each nybble.

Pebibyte

A pebibyte is a unit of data storage that equals 2 to the 50th power, or 1,125,899,906,842,624 bytes.

While a petabyte can be estimated as 10^15 or 1,000,000,000,000,000 bytes, a pebibyte is exactly 1,125,899,906,842,624 bytes. This is to avoid the ambiguity associated with the size of petabytes. A pebibyte is 1,024 tebibytes and precedes the exbibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: PiB
Petabyte

A petabyte is 2 to the 50th power, or 1,125,899,906,842,624 bytes. However, petabytes are often estimated as 10 to the 15th power, or 1,000,000,000,000,000 bytes. To avoid ambiguity, the exact calculation is often referred to as a pebibyte instead of a petabyte, though both definitions are commonly accepted.

A petabyte is 1,024 terabytes and precedes the exabyte unit of measurement. Since even the largest hard drives are measured in terabytes, petabytes are only used to measure the storage space of multiple hard drives or other collections of data. And no, "petabyte" is not what you do to make a byte purr.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: PB
String

A string is a data type used in programming, such as an integer and floating point unit, but is used to represent text rather than numbers. It is comprised of a set of characters that can also contain spaces and numbers. For example, the word "hamburger" and the phrase "I ate 3 hamburgers" are both strings. Even "12345" could be considered a string, if specified correctly. Typically, programmers must enclose strings in quotation marks for the data to recognized as a string and not a number or variable name.

For example, in the comparison:

if (Option1 == Option2) then ...

Option1 and Option2 may be variables containing integers, strings, or other data. If the values are the same, the test returns a value of true, otherwise the result is false. In the comparison:

if ("Option1" == "Option2") then ...

Option1 and Option2 are being treated as strings. Therefore the test is comparing the words "Option1" and "Option2," which would return false. The length of a string is often determined by using a null character.

Tebibyte

A tebibyte is a unit of data storage that equals 2 to the 40th power, or 1,099,511,627,776 bytes.

While a terabyte can be estimated as 10^12 or 1,000,000,000,000 bytes, a tebibyte is exactly 1,099,511,627,776 bytes. This is to avoid the ambiguity associated with the size of terabytes. A tebibyte is 1,024 gibibytes and precedes the pebibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: TiB
Terabyte

A terabyte is 2 to the 40th power, or 1,099,511,627,776 bytes.

It can be estimated as 10 to the 12th power, or 1,000,000,000,000 bytes. A terabyte is 1,024 gigabytes and precedes the petabyte unit of measurement. While today's consumer hard drives are typically measured in gigabytes, Web servers and file servers may have several terabytes of space. A single 500GB hard drive can also be called a half-terabyte drive.

The prefix "tera" comes from the Greek word meaning "monster." So, if you have a 500GB hard drive, you could say you have half a monsterbyte of disk space. If nothing else, it sure sounds impressive.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: TB

Yobibyte

A yobibyte is a unit of data storage that equals 2 to the 80th power, or 1,208,925,819,614,629,174,706,176 bytes.

While a yottabyte can be estimated as 10^24 or 1,000,000,000,000,000,000,000,000 bytes, a yobibyte is exactly 1,208,925,819,614,629,174,706,176 bytes. This is to avoid the ambiguity associated with the size of yottabytes. A yobibyte is 1,024 zebibytes and is the largest unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: YiB
Yottabyte

A yottabyte is 2 to the 80th power, or 1,208,925,819,614,629,174,706,176 bytes.

It can be estimated as 10 to the 24th power, or 1,000,000,000,000,000,000,000,000 bytes. The yottabyte is the largest unit of measurement for computer data, consisting of 1,024 zettabytes. Fortunately for those of us finite beings, yottabytes are not used very often. The prefix "yotta" was chosen since it is the second to last letter of the Greek alphabet. Though it seems more fitting that "yotta" refers to a "lotta" bytes.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: YB

Zebibyte

A zebibyte is a unit of data storage that equals 2 to the 70th power, or 1,180,591,620,717,411,303,424 bytes.

While a zettabyte can be estimated as 10^21 or 1,000,000,000,000,000,000,000 bytes, a zebibyte is exactly 1,180,591,620,717,411,303,424 bytes. This is to avoid the ambiguity associated with the size of zettabytes. A zebibyte is 1,024 exbibytes and precedes the yobibyte unit of measurement.

For a list of other units of measurements, view this Help Center article.

Abbreviation: ZiB
Zettabyte

A zettabyte is 2 to the 70th power, or 1,180,591,620,717,411,303,424 bytes.

It can be estimated as 10 to the 21st power, or 1,000,000,000,000,000,000,000 bytes. A zettabyte is 1,024 exabytes and precedes the yottabyte unit of measurement. Because of the enormous size of a zettabyte, this unit is almost never used. The prefix zetta comes from "Zeta," which is the sixth letter of the Greek alphabet.

For a list of all the different units of measurements, view this Help Center article.

Abbreviation: ZB