Which term is used to describe categorical values visualized for comparison purposes in a dataset?

The term used to describe categorical values visualized for comparison purposes in a dataset is indeed a bar chart. Bar charts are specifically designed to display and compare the frequencies, counts, or other measures of different categories. Each category is represented by a bar, and the length or height of the bar corresponds to the value associated with that category. This makes it easy to visually compare the size of the different categories against one another, highlighting differences in the data clearly.

Other visualization types mentioned serve different purposes. For instance, a histogram is used for showing the distribution of numerical data and does not apply to categorical values. A box plot is useful for visualizing the distribution of numerical data through their quartiles and identifying outliers, but it does not focus on categories for comparison. A line graph is primarily used to show trends over time for continuous data rather than categorical comparisons. Hence, the bar chart stands out as the most suitable and effective method for comparing categorical values in datasets.