Bit facts for kids

A bit is the smallest piece of information in a computer. Think of it like a tiny light switch that can only be in one of two positions: on or off. In computer language, "on" is usually represented by the number 1, and "off" is represented by the number 0.

Computers use these tiny "on" and "off" signals to store and process all kinds of data, from pictures and videos to text and games. Everything a computer does is built from these simple 0s and 1s.

What is a Bit?

A bit is a fundamental concept in the world of computers and digital information. It's short for "binary digit."

Binary Digits: 0s and 1s

In our everyday lives, we use a number system with ten digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9). This is called the decimal system. Computers, however, use a much simpler system called the binary system. This system only uses two digits: 0 and 1.

Each 0 or 1 is a single bit. Imagine a light bulb:

• If the light is off, it's like a 0.
• If the light is on, it's like a 1.

Computers use millions or even billions of these tiny "light switches" to represent everything.

Bits as a Unit of Data

When you hear about how much storage a computer has, like 1 gigabyte (GB) or 1 terabyte (TB), these measurements are based on bits. Bits are grouped together to make larger units of data:

• A group of 8 bits is called a byte.
• Bytes are used to represent things like a single letter, number, or symbol. For example, the letter 'A' might be represented by a specific pattern of 8 bits (one byte).

Larger units of data include:

• 1 kilobyte (KB) = 1,024 bytes
• 1 megabyte (MB) = 1,024 kilobytes
• 1 gigabyte (GB) = 1,024 megabytes
• 1 terabyte (TB) = 1,024 gigabytes

So, when you save a photo, it's stored as many bits and bytes. A high-quality photo might be several megabytes in size, meaning it's made up of millions of bits.

Bits as a Unit of Information

A bit can also measure the amount of information. If you have two equally likely choices, and you pick one, you've gained 1 bit of information.

For example:

• Imagine a coin flip. It can land on heads or tails. If someone tells you the result, you've received 1 bit of information.
• If you have four equally likely choices, you would need 2 bits of information to know the exact choice (because 2 bits can represent four different combinations: 00, 01, 10, 11).

This idea of information is important in fields like information theory, which studies how information is measured and communicated.

See also

• In Spanish: Bit para niños

Images for kids

• 

  A friendly robot representing technology and computing.