Every worksheet in Tableau contains shelves and cards, such as Columns, Rows, Marks, Filters, Pages, Legends, and more.
By placing fields on shelves or cards, you:
- Build the structure of your visualization.
- Increase the level of detail and control the number of marks in the view by including or excluding data.
- Add context to the visualization by encoding marks with color, size, shape, text, and detail.
Experiment with placing fields on different shelves and cards to find the optimal way to look at your data.
Tableau displays data using marks, where every mark corresponds to a row (or a group of rows) in your data source. The inner fields on the Rows and Columns shelves determine the default mark type. For example, if the inner fields are a measure and a dimension, the default mark type is a bar.