If you’ve ever looked at a computer and seen words like KB, MB or GB and thought “no idea what that actually means”, you’re not alone.
At the very smallest level, computers work in bits. A bit is just a 0 or a 1, like a tiny on/off switch.
A byte is a group of 8 bits bundled together. One byte is enough to store a single character like a letter, number or symbol.
From there, the sizes go up in steps. In computing we often use powers of 2, so the numbers look a bit odd:
- 1 kilobyte (KB) is about 1024 bytes
- 1 megabyte (MB) is about 1024 KB
- 1 gigabyte (GB) is about 1024 MB
- 1 terabyte (TB) is about 1024 GB
Rough idea of what that means in real life:
- A short text document might only be a few KB
- A photo from your phone might be a few MB
- Movies and games can be several GB
- A big external hard drive is often 1 or 2 TB
So next time you see “256 GB” on a device, that is just saying how many billions of bytes it can store.
