A byte of data has been stored in a number of different ways through the years as newer, better, and faster storage media are introduced. A byte is a unit of digital information that most commonly refers to eight bits. A bit is a unit of information that can be expressed as 0 or 1, representing a logical state. Let's take a brief walk down memory lane to learn about the origins of bits and bytes. Going back in time to Babbage's Analytical Engine, you can see that a bit was stored as the position of a mechanical gear or lever. In the case of paper cards, a bit was stored as the presence or absence of a hole in the card at a specific place. For magnetic storage devices, such as tapes and disks, a bit is represented by the polarity of a certain area of the magnetic film. In modern DRAM (dynamic random-access memory), a bit is often represented as two levels of electrical charge stored in a capacitor, a device that stores electrical energy in an electric field. In June 1956, Werner Buchholz coined the word byte to refer to a group of bits used to encode a single character of text. Let's address character encoding, starting with ASCII (American Standard Code for Information Interchange). ASCII was based on the English alphabet; therefore, every letter, digit, and symbol (a-z, A-Z, 0-9,, -, /, ",!, among others) were represented as a seven-bit integer between 32 and 127. To support other languages, Unicode extended ASCII so that each character is represented as a code-point, or character; for example, a lowercase j is U 006A, where U stands for Unicode followed by a hexadecimal number. UTF-8 is the standard for representing characters as eight bits, allowing every code-point from 0 to 127 to be stored in a single byte. This is fine for English characters, but other languages often have characters that are expressed as two or more bytes.

Just as oil propelled Standard Oil Co. Inc. to a position of dominant industrial power in the late 1800s, data is doing the same for a number of technology firms today. Half of consumer online spending in the U.S. is controlled by Amazon, a company that relies extensively on mining data so it knows what you want before your buy it.