What is the purpose of a parameter in Tableau?

A parameter in Tableau serves the specific purpose of allowing user-driven selections. Parameters are versatile tools that enable users to input values dynamically, which can then be used in calculations, filters, or reference lines. When a parameter is created, it can be designed to allow users to select from a predetermined list of options or to input a value directly. This interactivity empowers users to customize their views and analyses, effectively allowing for real-time adjustments based on their selections.

For instance, a parameter could allow a user to choose a specific sales region, which would then adjust the displayed data across various visualizations, providing a tailored look at the performance data for only that region. This functionality goes beyond simple filtering, as it can influence calculations or manipulate different aspects of the visualization in real time, making it an invaluable component for enhancing user experience and interactivity within Tableau dashboards.