What's a bitcoin miner

       ... or, "why does my computer fan turn on when I visit that website?"

If you're here, you probably followed a link from a website using Bitcoin Plus for websites. To find out why your computer fan turned on, first you need to know about bitcoin:

Bitcoin is a new online currency. It can be created (yes, the currency can be created) by a piece of software called a bitcoin miner.
Your computer fan turned on because generating bitcoin takes computer power. It's essentially generating money to help support the website you came from.

It's nothing to be alarmed at, it will not slow down your computer because it only uses spare computer power.
If you like, you can learn more about bitcoin.

If you're annoyed by this, feel free to complain to me at donny@bitcoinplus.com.