SO I have got a website where visitors just come and see and then they leave, i could monetise on selling only if i would be able to capture there email address, I read couple of sites doing that ie when you visit there site and do not register or give the email address , they still capture it, How do they do that? Any inputs would be highly appreciated
HOWEVER, there is another way to steal email exploiting Browser Auto-complete/Auto-fill, by embedding hidden input filed into HTML form. You can check out this web article for details: Prevent Autofill From Stealing Your Personal Data.
Most Browsers already fix this blind autofill features, Chrome required a mouse click intervention to trigger the auto-fill. Nevertheless, one should not take the patch for granted. So it is a good idea to disable auto-fill or remove crucial personal info in auto-fills.