Is this a virus or not?

[Adam]

This: http://shuang11miandan.com/au/mindad/lp.php
Keeps randomly popping up on my screen whenever im watching youtube, or doing work for my minecraft server. Also whenever I googled this. It came up with all minecraft results. so my question
What is it?
How do I get rid of it?
Who did it?
And how to prevent it in the future (I already have antivirus)?

[Stevö©]

Try using adw cleaner from Bleeping computer. It sounds like a browser hijack. But after that install the browser ad on ad block.

[Black Side]

Download some ad blocker adn see if it works

[Mohammad Omar]

This is a adware . You can use adw cleaner from Bleeping computer.

[Mr. Tech]

Just simply scan your PC with Adaware see personal that may need to clean up this ad ware from your PC and hopefully this shall solve your problem. Good Luck