A 'Tag' in web analytics refers to a snippet of code placed on a webpage to collect data and integrate third-party services, such as analytics tools, ad platforms, or social media buttons.

Tags are essential for tracking user interactions, understanding website performance, and enhancing marketing efforts. They allow for the collection of rich, detailed data about how users interact with a site, which can be used to inform decisions and improve user experience.

The use of tags has become increasingly sophisticated, allowing for advanced tracking and personalization of user experiences. Tags can trigger specific actions or gather particular types of data, making them invaluable tools in the modern digital marketing landscape.