CPM stands for Cost Per Mille, which is a common advertising metric used to measure the cost of displaying an advertisement to one thousand (1,000) people or impressions. In other words, it measures the cost of an ad per thousand impressions. CPM is commonly used in digital advertising, such as display ads, social media ads, and video ads. It's one way for advertisers to understand how much they are paying for each impression, and to compare the cost of different ad placements or campaigns. For example, if an advertiser pays $10 CPM for a banner ad on a website, it means that they are paying $10 for every 1,000 times that the ad is displayed on that website. If the ad is displayed 10,000 times, the total cost to the advertiser would be $100. CPL stands for Cost Per Lead, which is an advertising metric used to measure the cost of acquiring a lead or potential customer. In other words, it measures the cost of an ad campaign per lead generated. CPL is commonly used in online marketing campaigns, where the goal is to generate leads, such as for a newsletter sign-up or a free trial. Advertisers pay for each lead that they acquire, with the cost of each lead depending on the specific campaign and the quality of the leads generated. For example, if an advertiser pays $5 CPL for a campaign and generates 100 leads, the total cost to the advertiser would be $500. The quality of the leads generated can vary, with some leads more likely to convert to customers than others, which is why it's important to measure the quality of leads as well as the cost per lead.