CPC or cost-per-click is a popular term used in digital advertising to describe the amount of money an advertiser pays every time someone clicks on their ad. There are several synonyms for CPC, such as pay-per-click (PPC), cost-per-engagement (CPE), and cost-per-action (CPA). PPC is used interchangeably with CPC, and both represent the same concept of paying for clicks on an ad. CPE refers to the cost incurred in case a user takes any other action apart from clicking, like watching a video or filling a form. Lastly, CPA describes the cost paid by the advertiser when a user performs a desired action, like making a purchase or filling a form.