SITES USE YOUR CPU POWER FOR MINING !

websites like piratebay use your cpu to mine cryptocurrency like bitcoin litecoin etc...
Solutions :
extensions for google chrome

1. https://chrome.google.com/webstore/detail/no-coin-block-miners-on-t/gojamcfopckidlocpkbelmpjcgmbgjcl
   OR
   2)https://chrome.google.com/webstore/detail/minerblock/emikbbbebcdfohonlaifafnoanocnebl