How to Google detected that is is Paid links on site. because in paid link it is money related Website (A) direct link to website (B) & no any related link between it that it has Paid link. but how to Google find it out.
I think they usually look out if there is any link exchange between websites. For example if google sees a backlinks on a PR 5 website for a PR 0 or PR 1 website and the website is non related and there is no link exchange between them, then it should consider the backlink a paid one.
Firs most of the paid link is given by low PR sites and to earn money only from it. So it may be a reason for it. And every site has a limited number of outbound link. So that if any site across this limit count as a black listed site. And if you are taking link from that site may be consider as a paid link. I think that these are reason for It.
What the hell are you all talking about??? No-one knows if a link is paid or not! Ya, google, be it algorithmically or manually, may have some time of guessing but if done correctly I think it is impossible to detect 100% a link as paid (not that they need it or care...). I myself have few outgoing links from my sites - not paid, just related to the topic and with the only idea to provide better experience for my visitors. Example: I post on my home pages news about events in particular destinations(cities/towns/resorts). These are short and I cannot give a total info, full schedules and accurate details - that will end up as a huge home page and no I do not want to put these in inner dedicated pages, so I add a link to the official organizer/site. Now what is this - a paid link or a natural one? I do not buy links for my sites as I do not need to, but since I joined DigitalPoint I have bought TONS, I mean TONS of links for clients' sites during the last several years and not single one have got caught or experienced any kind of penalty. Also selling links for one client - no problem at all! (cool) Pity, but that market is in terrible state at the moment. Most offers are some f*****g huge lists and crappy, dropped domains or just scammer-sellers.... Still there are some good offers and serious guys to deal with p.s. Hah, still remember a client's sentence: "quality, not quantity" - about paid links. I think that was quite correct in regard of the Penguin updated that followed, although it made google's results so bad that even if I was able to make a search engine it would have been returning better results