Binary

Binary

Binary is a number system that contains two digits, 0 and 1 (also known as base 2). A binary digit (or bit) is the smallest unit of data in computing.

Bits and Bytes

Bits can be grouped together to make them easier to work with: 1) Nibble - 4 bits 2) Byte - 8 bits 3) Kilobyte (KB) - 1024 bytes 4) Megabyte (MB) - 1024 kilobytes 5) Gigabyte (GB) - 1024 megabytes 6) Terabyte (TB) - 1024 gigabytes

Character Sets

Just like numbers, text needs to be stored as a binary code too. A character set is a defined list of characters represented by a computer hardware and software. Each letter is assigned a particular binary code (e.g. ASCII and Unicode).

Kilobyte (KB)

1024 bytes (or 1024*8 bits)

Terabyte (TB)

1024 gigabytes

Megabyte (MB)

1024 kilobytes (or 1048576 bytes)

Gigabyte (GB)

1024 megabytes

Nibble

4 bits

Byte

8 bits

Non-Volatile Memory

Non-volatile memory saves information regardless of whether the power to the computer is on or off. Its content cannot be changed.

RAM (Random Access Memory)

RAM is the main place for storing instructions and data whilst a program is being executed. Program data is copied into the RAM before the CPU can run the program. RAM is memory that is constantly being written to and read from. It does not retain its contents without a constant supply of power.

What is the difference between RAM and ROM?

RAM is volatile memory, whereas ROM is non-volatile memory.

ROM (Read Only Memory)

ROM is a flash memory chip that contains a small amount of non-volatile memory. It is extremely useful for when we need data that is a constant.

ASCII (American Standard Code for Information Interchange)

The ASCII character set is a 7-bit set of codes that allow 128 different characters. That is enough for every uppercase and lowercase letter, digit, punctuation mark and non-printing character such as a line break and a carriage return.

Hexadecimal

The hexadecimal is a number system is a type of number system, that has a base value equal to 16 (also known as Base 16) represented by only 16 symbols. These symbols or values are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F. Each digit represents a decimal system value.

Volatile Memory

Volatile memory only stores information to run programs whilst the computer is on.

Decimal

Decimal is a positional number system employing 10 as the base number (also known as Base10) and represented by 10 different numerals, the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.