PTC site means Paid to Click Sites.
Paid To Click or PTC websites are the easiest way to earn money online. These websites let you make money without extra effort, require no skills, and are free. All you have to do is click a few ads, read a few mails or complete a few surveys.
Many paid to click websites require you to click on an ad and view it for about 30 seconds to get paid. When your account balance reaches the minimum payout value, you can request for a payout. Payments are generally made to a PayPal or AlertPay account. Staying active in a number of these programs lets you earn steady and regular online income. However, due to the boom in PTC industry, there are more scams out there than genuine sites.
PTC-RefBack offers you the unique chance to work at western PTC-sites and to be paid for surfing of sponsor ads. This is a professional project, that pays for your affiliation.