Bits and Bytes

A Simple Understanding of Bits and Bytes

When it comes to running a business, everything is measurable. From the hours on your employee’s time card to data stored on your network, you can be sure there is a way for it to be quantified. For time, we know seconds and minutes, but how do you measure data? Bit by byte.

When you go to buy a computer, some of the first information you’ll see is the size of the hard drive and the measure of random access memory (RAM). You’ll see numbers like 500GB or 2TB, and if you don’t know about computers, or more specifically, data, you would have trouble understanding what those numbers mean.

A bit is a binary digit, the smallest increment of data on a computer. A bit can hold only one of two values: 0 or 1, corresponding to the electrical values of off or on, respectively.

Bits and Bytes by the Numbers

Every byte consists of eight bits. So, you’d think that a kilobyte would be 1,000 bytes, right? Not exactly. Remember, computers operate using the binary system. That means hard drives, memory, and bandwidth are measured in powers of two. Going back to the kilobyte example: 2 ^ 10 equals 1,024, not 1,000.

A kilobyte (KB) is 1,024 bytes, not one thousand bytes as might be expected, because computers use binary (base two) math, instead of a decimal (base ten) system.

Computer storage and memory is often measured in megabytes (MB) and gigabytes (GB). A medium-sized novel contains about 1 MB of information. 1 MB is 1,024 kilobytes, or 1,048,576 (1024x1024) bytes, not one million bytes.

Bit

• a “bit” is atomic: the smallest unit of storage
• A bit stores just a 0 or 1
• “In the computer it’s all 0’s and 1's” … bits
• Anything with two separate states can store 1 bit
• In a chip: electric charge = 0/1
• In a hard drive: spots of North/South magnetism = 0/1
• A bit is too small to be much use
• Group 8 bits together to make 1 byte

Bytes

• “Byte” — unit of information storage
• A document, an image, a movie .. how many bytes?
• 1 byte is enough to hold about 1 typed character, e.g. ‘b’ or ‘X’ or ‘$’
• All storage is measured in bytes, despite being very different hardware
• Kilobyte, KB, about 1 thousand bytes
• Megabyte, MB, about 1 million bytes
• Gigabyte, GB, about 1 billion bytes
• Terabyte, TB, about 1 trillion bytes (rare)