Apsense

Some time ago I found a site that frankly at that time I did not quite understand what it is, but I still register there, until my membershipfor some time to let it alone but over time I became curious about the site and trying to figure out what is the function of the site, after Ilearned little by little so it will understand its function. There is a name that is APSENSE.COM,
and the link is:  http://www.apsense.com/invite/yadimld1?url=[TARGETURL]