Cost Per Click is a pay-per-click (PPC) pricing model where advertisers pay a fee each time one of their ads is clicked. It's commonly used in search engine advertising and social media advertising.

Formula: CPC = Total Cost of Clicks / Number of Clicks

Key points:

• CPC can vary based on factors like keyword competitiveness, ad quality, and target audience
• In some platforms, advertisers bid on keywords in an auction-style system
• Lower CPC doesn't always mean better performance - it's important to consider the quality of traffic and eventual conversions

Relationship to other metrics:

CPC is often used in conjunction with CTR and conversion rate to assess the overall effectiveness of an ad campaign.