Nominal data, also called categorical data, does not have does not have a natural sequence. Instead, the data is typically in named categories or labels without numeric significance.
For example, a survey question that asks for a favorite beverage, with choices of coffee, tea, water, or milk will generate nominal data in 4 categories as in the above bar chart.
When you hear "nominal", think "named" as in "named categories". Other examples of nominal data would be male/female, eye color, make of car, etc.