CPC stands for Cost Per Click. In another context, it can also be called pay per click.
Cost per click refers to paid search ads.
Each advertisement that is clicked will be charged towards your advertising budget, including paid search ads, display ads, and carousel ads.
For these advertisements, you will need to go through Google Ads and bid for specific ad positions. On Google Ads, the max. CPC refers to the highest amount that you are willing to pay for a click on your advertisement. You can also use Enhanced CPC which is a bid strategy implemented by Google to help you maximize your conversions. You can also purchase advertisements for Facebook with the CPC method as well.