Which of the following describes a bar chart?

A bar chart is indeed defined as a graphical device specifically designed to represent categorical data visually. It uses bars of varying lengths to illustrate the frequency or magnitude of different categories, making it easier to compare these categories at a glance. Each category is represented by a bar, and the height or length of the bar reflects the value associated with that category.

By employing a bar chart, viewers can quickly identify trends, patterns, or outliers within the data presented. This visual representation is particularly helpful for illustrating qualitative or nominal data, where numeric comparisons may not be as straightforward. Hence, describing a bar chart as a graphical device for depicting categorical data accurately captures its essence and function.

The other options do not encompass the concept of a bar chart effectively. A table merely summarizes data but does not provide a visual representation. Statistical analysis methods do not specifically refer to visual tools but rather to techniques used in analyzing data. A survey tool is utilized for data collection rather than for presenting or visualizing data, which again doesn't fit the description of a bar chart.