How many bits in the byte? What is a bit and byte?

All photos, text documents and programs are stored in computer memory in the form of bits and bytes. What are these smallest pieces of information and how many bits in a byte?

Storing data in memory

Computer memory is a huge collection of cells filled with zeros and ones. A cell is the minimum amount of data that a reader can access. Physically, it is a trigger (in modern computers). The trigger is so small that it is difficult to see even under a microscope. Each cell has a unique address, through which it finds a particular program.

Under the cell in most cases, understand one byte. But, depending on the bit depth of the architecture, it can combine 2, 4 or 8 bytes. Byte is perceived by electronic devices as a whole, but in fact it consists of even smaller cells - bits. In 1 byte, you can encode a character, for example, a letter or number, while 1 bit is not enough for this.

Controllers rarely operate with separate bits, although technically this is possible. Instead, it accesses whole bytes or even byte groups.

What is a bit?

Often a bit is understood as a unit of measurement of information. This definition can not be called exact, because the very concept of information is blurred enough. If to speak more correctly, the bit is the letter of the computer alphabet. The word "bit" comes from the English expression "binary digit", which literally means "binary digit".

The alphabet of computers is simple and consists of only two symbols: 1 and 0 (presence or absence of a signal, true or false). This set is enough to logically describe everything, anything. The third state, by which one understands the silence of the computer (stopping the transmission of signals), is a myth.

The letter itself does not carry any value in terms of information: looking at a unit or zero, it is impossible to understand even what kind of data this value refers to. And photos, and texts, and programs ultimately consist of units and zeros. Therefore, the bit is inconvenient as an independent unit. Therefore, the bits need to be combined in order to encode useful information with them.

What is a byte?

If a bit is a letter, then the byte is a kind of word. One byte can contain a text symbol, an integer, a part of a large number, two small numbers, etc. Thus, the byte already contains meaningful information, albeit in a small amount.

Beginners programmers and just curious users are interested in how many 1 byte of bits. In modern computers, one byte is always equal to eight bits.

If a bit is capable of receiving only two values, then a combination of eight bits can create 256 different combinations. The number 256 is formed by the construction of a deuce in the eighth power (in accordance with how many bits in the byte).

One bit is 1 or 0. Two bits can already create combinations: 00, 01, 10 and 11. When it comes to 8 bits, then the options for combining zeroes and ones in the range 00000000 ... 11111111 is just 256. If you remember , How many values can take and how many bits are contained in one byte, then remembering this number will be very easy.

Each combination of symbols can carry a variety of information, depending on the encoding (ASCII, Unicode, etc.). That's why users are faced with the fact that the information entered in the Russian language is sometimes displayed in the form of intricate symbols.

Features of the binary system

The binary system has all the same properties as the usual decimal: numbers consisting of ones and zeros can be added, subtracted, multiplied, etc. The only difference is that the system consists not of 10, but only of 2-digit number. That's why it's convenient to use to encrypt information.

In any position system of the calculus, the numbers consist of the digits: units, tens, hundreds, etc. In the decimal system, the maximum value of one digit is 9, and in the binary system - 1. Since one bit can take only two values, binary numbers quickly Increase in length. For example, the usual number 9 will be written as 1001. This means that the nine will be written with four symbols, with one binary symbol corresponding to one bit.

Why is the information encrypted in binary form?

Decimal system is convenient for input and output of information, and binary for organizing the process of its transformation. Also very popular are systems that contain eight and sixteen characters: they translate machine codes into a convenient form.

The binary system is most convenient from the point of view of logic. The unit conditionally means "yes": there is a signal, the statement is true, etc. Zero is associated with the value "no": the value is false, there is no signal, etc. Any open question can be transformed into one or more questions with answer variants "yes " or not". The third option, for example, "unknown", will be absolutely useless.

In the development of computer technology, three-digit storage capacities for information, called trits, were developed. They can take three values: 0 - capacity is empty, 1 - capacity is half full and 2 - full capacity. However, the binary system turned out to be simpler and more logical, therefore it gained much more popularity.

How many bits in the byte was before?

Earlier it was impossible to say unequivocally how many bits in the byte. Initially, a byte was understood as a machine word, that is, the number of bits that a computer can process in a single working cycle (cycle). When computers still did not fit in the workstations, different microprocessors worked with bytes of various sizes. The byte could include 6 bits, and the first IBM models had a size of 9 bits.

Today, 8-bit bytes have become so familiar that even in the definition of a byte it is often said that this is a unit of information consisting of 8 bits. However, in a number of architectures, a byte equals 32 bits and acts as a machine word. Such architectures are used in some supercomputers and signal processors, but not on the computers, laptops and mobile phones that are familiar to us.

Why won the eight-bit standard?

Bytes purchased an 8-bit size due to the IBM PC platform with the most popular 8-bit Intel 8086 processor. The prevalence of this model contributed to the fact that in the 1970s, The 8 bits in the byte actually became the standard value.

The eight-bit standard is convenient in that it allows you to store two decimal system symbols in 1 byte. With a 6-bit system, one digit can be stored, while 2 bits are superfluous. In 9 bits, you can write 2 numbers, but still one extra bit is left. The number 8 is the third power of two, which provides additional convenience.

Areas of use of bits and bytes

Many users wonder: how not to confuse the bit and byte? First of all, it is necessary to pay attention to how the designation is written: abbreviated byte is written in the form of a capital "B" (in English - "B"). Accordingly, to indicate the bit is a small letter "b" ("b").

However, there is always a possibility that the register is not selected correctly (for example, some programs automatically translate all text into lowercase or uppercase). In this case, you should know what it is usual to measure in bits, and what - in bytes.

Traditionally bytes measure volumes: the size of the hard disk, flash drive and any other media will be specified in bytes and enlarged units, for example, gigabytes.

Bits serve to measure speed. The amount of information that a channel skips, the speed of the Internet, etc. are measured in bits and derived units, for example, megabits. The speed of downloading files is also always displayed in bits.

If desired, you can convert the bits to bytes or vice versa. To do this, it is enough to remember how many bits are in the byte, and to perform a simple mathematical calculation. Bits are converted into bytes by dividing by eight, the reverse translation is performed by multiplying by the same number.

What is a machine word?

A machine word is information stored in a memory location. It is the maximum sequence of units of information that is processed as a whole.

The length of the word corresponds to the length of the processor, which for a long time was 16 bits. In most modern computers, it is 64 bits, although there are shorter (32 bits), and longer machine words. In this case, the number of bits forming a computer word is always a multiple of eight and can be easily converted into bytes.

For a particular computer, the word length is unchanged and belongs to a number of the most important characteristics of the "hardware".