Advertising Glossary
Plain-English definitions of the metrics, concepts, and technologies that matter for modern digital advertising.
Attribution Window
An attribution window (also called a lookback window or conversion window) is the time period after a user interacts with an ad during which a subsequent conversion can be attributed to that ad.
Read definitionClick-Through Rate (CTR)
Click-Through Rate (CTR) is the percentage of impressions that result in a click. It is calculated by dividing the number of clicks by the number of impressions and multiplying by 100.
Read definitionConversion API (CAPI)
A Conversion API (CAPI) is a server-side tracking method that sends conversion events directly from your server to an ad platform's servers, bypassing browser-based tracking limitations like cookie blocking and ad blockers.
Read definitionCost per Acquisition (CPA)
Cost per Acquisition (CPA) is the average amount you spend on advertising to generate one conversion, whether that is a purchase, a lead, a signup, or any other defined action.
Read definitionCreative Fatigue
Creative fatigue is the decline in ad performance that occurs when your target audience has seen the same ad too many times, leading to lower engagement and higher costs.
Read definitionFrequency Capping
Frequency capping is an ad delivery setting that limits the maximum number of times a single user can see your ad within a defined time period, preventing overexposure and creative fatigue.
Read definitionGoogle Ads Query Language (GAQL)
Google Ads Query Language (GAQL) is a SQL-like query language used to request data from the Google Ads API. It lets you select specific fields, apply filters, and order results from any Google Ads resource.
Read definitionLookalike Audience
A lookalike audience (also called a similar audience) is a targeting option that uses machine learning to find new people who share behavioral and demographic characteristics with your existing customers or high-value users.
Read definitionModel Context Protocol (MCP)
Model Context Protocol (MCP) is an open standard created by Anthropic that lets AI assistants connect directly to external tools and data sources through a universal interface.
Read definitionReturn on Ad Spend (ROAS)
Return on Ad Spend (ROAS) is a marketing metric that measures the revenue earned for every unit of currency spent on advertising. A ROAS of 4x means you earn four dollars for every dollar spent.
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