Using a chart to present data for a school project or work presentation can help ensure the significance of the information is conveyed to the audience. A variety of chart types can present data -- pie charts, line charts, bar graphs -- in different ways. However, the overall consideration of using a chart to present data has its own advantages and disadvantages. A person considering a chart should weigh those before making one.
One of the greatest advantages of using a chart is that it makes information visually interesting to the audience. A table full of numbers may contain exactly the same information as a chart, but it is more difficult for an audience to easily absorb and comprehend. In contrast, a chart provides a quick, direct way to present information, in a way that is visually dynamic and of interest to the audience.
Another advantage of using a chart is that, depending on the type chosen, it can directly emphasize the key findings of the data for the audience. For example, if the data indicates how much of a certain product is sold in the store, a pie chart could make that readily apparent. If a pie chart shows one section, which represents one product, accounting for the vast majority of the whole, the audience will immediately perceive that and absorb its implications. In contrast, a table of data may also indicate high sales for that particular product, but it will not drive home the significance of that information like a chart would.
Lack of precision
A disadvantage of using a chart is that, by design, a chart will likely not be as precise as the raw data. The data that would make up the chart includes the numbers that make up the data, which is as accurate as it gets. However, when you transfer that information into a chart, it decreases the specificity of that information. A bar graph can quickly indicate that one category exceeds another, but exactly how much one exceeds the other will not be as apparent as it would be with the raw data.
One disadvantage to charts is that it can simplify the information, making some of its more complicated aspects less apparent. A chart is more visually interesting and makes apparent the significant portions of the data, but it does so by emphasizing particular features of the data. While charts excel at presenting the data in certain ways, it also means that charts struggle to highlight various aspects of the data for which they are not designed.