Paid to click means literary what is sais; You get paid to click on links that adverisers want you to see.

Adertisement can be very expensive, this is where PTC (Paid to click) programs comes in. You can advertise your websites to 1000s of unique users for just a couple of dollars. what's greate is that un matter what you get a 100% CTR ( click through rate ) where each click can cost as little as 0.00001. This gives everyone a chance to display their ads and make money from it.