Pay-per-click (PPC)
The ad model where you are billed only when someone clicks, not when your ad is merely shown.
See it
What it is
PPC is a billing model: the platform shows your ad as often as it likes, and you are charged only when somebody clicks. Impressions are free. The canonical home is paid search (Google Ads, formerly AdWords, and Microsoft Ads), which is why people often say PPC when they mean 'search ads' in general, but the same model runs across shopping ads, many social placements, and marketplaces like Amazon.
Placement is an auction, not a price list. Every query runs one, and where you land depends on more than money: platforms weigh your bid against their own quality and eligibility signals, plus format, device, and context. On Google that bundle includes Quality Score (expected CTR, ad relevance, landing page experience). It is not one tidy multiplication, the ingredients differ per platform, and none of them publish the real weights, but the direction holds: better ads generally pay less for better slots. Reach for PPC when demand already exists and you want in front of it this week, since people searching 'best invoicing app for freelancers' have told you exactly what they want.
Gotcha: PPC is the model, CPC is the price, and CPA is what you actually care about. The two ways to burn money here are broad match keywords quietly buying irrelevant searches, and sending every ad to the homepage instead of a page that repeats the ad's promise word for word.
Ask AI for it
Build a paid search results mock for [product] targeting the query '[keyword]'. Render a search results page containing three sponsored listings above two organic results: each sponsored listing has a bold 'Sponsored' label, a 30-character headline, a display URL, a 90-character description, and two sitelink rows. Style it like a desktop search engine result page: system sans-serif, blue link headings, muted green URLs, generous line height, no card borders. Underneath, show a small auction panel listing each advertiser's max bid, quality input, resulting rank, and price paid per click, computed with [defined formula] and labeled on screen as a simplified illustration built for teaching. Do not present it as any platform's actual pricing algorithm.