I just had a great idea make a site that has games or videos or something that people enjoy on the internet and mine for coins using their computer.Assuming that it is possible to do that.
I think they really use your computer to mine coin
Not sure if this is even possible, but definitely an entertaining idea.Long story short: HTML browsers weren't made for games. We use HTML5 canvas for drawing the graphics, and that's very CPU intensive on older machines. We could/should switch to WebGL, which is faster, but then there are compatibility problems with older machines.
In short: if you want fancy graphics, you pay for it.
When I open this site my computer freeze.
It is possible to mine bitcoin using a browser. Bitcoinplus.com has webminer I even tried it to my forum in 2012 but many visitors complain.
Of course it is possible to mine in a browser, as on anything where you can execute the relevant code (mainly SHA256). It is just absolutely *incredibly* inefficient. You would need to mine in javascript, good luck with that
(Note that "javascript in a browser" mining is practically completely useless even for CPU-targeted POW functions such as primecoin).