You have probably heard about Cryptocurrencies like Bitcoin, Ethereum, XRP etc. They are thousands in number, among them Bitcoin, Ethereum and XRP are most mined cryptocurrencies. Cryptocurrencies are decentralized currency that can be accessible in unlimited amount by anyone who spends time and energy to mine it.
Cryptocurrencies are mined by solving some math problems and the problems are to find some HAS. If you got the HAS you got the Bitcoin. It takes millions of billions of attempt to find a single HAS. This is why Bitcoin mining costs lots of power and time. Same happens to your PC if some websites start to mine bitcoin using your CPU.
Similarly there are 2500+ websites that mines cryptocurrencies from their visitors. Some websites are
The Pirate Bay (http://thepiratebay.org)
How to detect if a website is using your CPU?
It is very easy to detect if a website is mining cryptocurrencies using your PC’s CPU. You PC may become hot if mining script uses CPU heavily. In chrome press Shift + Esc to open task manager. In the task manger you can see which process is consuming your CPU.
How to avoid cryptojacking?
You can use extension that blocks cryptocurrency mining. minerBlock for Chrome, NoCoin for Chrome, NoScript Security Suite for Firefox can be used to avoid mining. Anti-WebMiner for Windows blocks mining scripts in all browser. Also installing anti-malware apps like MalwareBytes protects you from cryptojacking.