There are five Mark properties always available: Color, Size, Text/Label, Detail, and Tooltip. There are also three properties available only when using a specific Mark type: Shape, Path, and Angle. 

Any field used in a Mark property splits the number of Marks if it returns more than one value (except for the Tooltip). For example, if you put a Dimension that contains three different values on Color, the number of Marks is split by three. If you have more than one Dimension in Mark Properties, the number of Marks are defined by the number of existing combinations of the different Dimensions.

Let's see in detail each Property with the different options you have to make better visualizations. Again, for each Property you'll find an example that you can reproduce with Sample - Superstore by adding the fields on the same shelves as in the image.

Let's start with the most used property, Color.