Importance of Visuals in Technical Communication
Most technical communications require more than text to concisely and accurately communicate concepts or techniques. Visual elements such as graphs, charts, tables, photographs, diagrams, and maps capture your readers’ attention and help them to understand your ideas more fully. They are like the illustrations that help tell the story. Visuals augment your written ideas and simplify complicated textual descriptions. They can help a reader understand a complicated process or visualize trends in the data. The key concept to remember here is that visuals clarify, illustrate, and augment your written text; they are not a replacement for written text. The old adage, “a picture is worth a thousand words” does not hold true in technical writing, but adding visuals may save you a hundred words or so of additional explanation and clarification. If you have visual elements in your document, they must be based on and supplement your written content, even those that are used simply to visually break up text.
Visuals are important in explaining information to an audience. The human brain is programmed visually; it “processes images 60 times faster than text, and 90 percent of the information transmitted to the brain is visual.” [1] According to How People Learn:
Different features of learning contribute to the durability or fragility of memory. For example, comparisons of people’s memories for words with their memories for pictures of the same objects show a superiority effect for pictures. The superiority effect of pictures is also true if words and pictures are combined during learning (Roediger, 1997). Obviously, this finding has direct relevance for improving the long-term learning of certain kinds of information. [2]
Offering information graphically plays on the propensity of the brain for images, and can help your audience process and recall information. Graphics can make large amounts of data accessible to your reader. However, graphics have to be created properly in order to aid understanding. Crowded or busy graphics can leave readers more confused than they were before. Graphs drawn incorrectly may cause readers to draw inaccurate conclusions. Data can be used to mislead readers when not represented responsibly. Create or choose visuals based on their ability to accurately communicate and enhance your information for your purpose and audience.
Types of Visuals
Visuals are classified into two large categories, Tables and Figures. Here’s an overview; subsequent pages in this section go into more detail about how to create tables and figures.
Tables
Tables organize data in volumes and rows using numbers and words. Tables present data logically, and usually are used to compare data. Here’s a table that identifies and describes visuals commonly used in technical writing.
| Type of Visual | Description and Purpose | |
|---|---|---|
| Tables | Place detailed data/information in categories formatted into rows and columns for comparison; use when exact figures are important. Label column headings (box heads) and/or rows (stubs). | |
| Graphs | Bar Graph | Compare and contrast two or more subjects at the same point in time, or compare change over time. |
| Column Graph | Reveal change in a subject at regular intervals of time. | |
| Line Graph | Show the degree and direction of change relative to two variables; compare items over time, show frequency or distribution, or show correlations. | |
| Charts | Pie Chart | Display the number and relative size of the divisions of a subject; shows relation of parts to a whole (parts must sum to 100% to make sense). |
| Org. Chart | Map the divisions and levels of responsibility or hierarchy within an organization. | |
| Flow Chart | Show the sequence of steps in a process or procedure. | |
| Gantt Chart | Indicates timelines for multi-stepped projects, especially used in proposals and progress reports. | |
| Illustrations | Diagram | Identify the parts of a subject and their spatial or functional relationship; emphasize detail or show dimensions. |
| Photo | Show what a subject looks like in realistic detail or show it being used. | |
| Drawing |
Simplify an item to explain that item’s characteristics. | |
| Animation | Simulate a process, operation, or incident. | |
| Film clip | Depict a process, operation, or incident in realistic detail. | |
Figures
Figures illustrate all other types of data. Figures include such visuals as pie charts, line graphs, bar graphs, diagrams, flow charts, drawings, and photographs. Here’s some of the same information from the table above presented in different form, so that you can compare tables and figures and how they present information. Note that the only rule for choosing a type of visual is that it needs to be appropriate for your purpose and audience.
Pie Charts show pieces of a whole, and the relative size of divisions of that whole.
Line graphs show the degree and direction of change between two variables.
Horizontal Bar Graphs compare and contrast two or more subjects.
Vertical Bar Graphs compare and contrast two or more subjects, and may compare change over time.
Diagrams show spatial and/or functional relationships.
Organizational and Flow Charts show reporting structures (organizational chart) and the sequence of steps in a process or procedure (flow chart).
Drawings simplify an item to more effectively explain that item’s characteristics.
Photographs show what something looks like in realistic detail.
The following video reviews important concepts about graphics and also provides useful examples of what not to do in visuals.
[1] http://www.t-sciences.com/news/humans-process-visual-data-better Eisenberg, Harris. “Humans Process Visual Data Better.” Thermopylae website. Published September 15, 2014.
[2] Bransford, John D., Brown, Ann L., Cocking, Rodney R., editors. Mind and Brain Chapter, How People Learn: Brain, Mind, Experience, and School. Consensus Study Report, The National Academies of Sciences, Engineering, Medicine, 2020. https://www.nap.edu/read/9853/chapter/8
