Thumbnail gallery post

A thumbnail gallery post (TGP) is a common type of ad-driven website that provides links to free Internet pornography. In affiliate marketing terms, TGPs are the affiliates that drive new traffic to the product producers, paysites. Paysites offer free hosted galleries (FHGs) in an effort to attract paying customers, and it is these FHGs, as well as chains of TGPs, that a TGP links to.

TGPs employ a variety of schemes to trade traffic with other TGPs; signing up for these trades is usually easy and free for other TGP owners. Perhaps the most basic trade is to link to other TGP sites.

These trades are reciprocal: by looking at the referrer header of the HTTP requests, a TGP owner knows where their traffic comes from; a site that doesn't provide enough visitors will be excluded from further trades. Both of these traffic trade schemes are therefore susceptible to cheating: a trader can use so-called hitbots to create bogus traffic from his site to another, in order to get good traffic in return.

Scripts that automate the maintenance of a TGP, manage traffic trades and protect against hitbots are readily available. Some of these are even free, financed by an occasional redirecting of surfers to a site under the control of the script's programmer, or by advertisements directed at other webmasters on the gallery submission and traffic trade pages.

The success of the TGP format forced some adult webmasters to rethink their role in promotion of commercial sites. Some webmasters believe that TGPs saturate the Internet with free pornography. A new format for organizing previews was tried. This format, named TGP2, limits the exposure of the surfer to free content in many ways. For example, no more than 12 thumbnails are allowed per page, of which only 5 can link to images (and not directly, but to pages with images and ads) and the rest must link to signup pages. Per the standard, TGP2 galleries only include softcore images and may not link to TGP sites. Most TGP sites do not allow TGP2 galleries to be listed. The concept received little approval among web surfers and high traffic levels were never achieved.

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Wikipedia