Our objective today is to help you use graphs and charts effectively. The language that you're going to practice in this module is very important, not only when you give presentations, but also in discussions and reports that are just a part of your daily work. We'll start by talking about the language used to describe graphs and charts, and then we'll work on using large numbers accurately, and last, we'll study the vocabulary we use to describe trends. Okay, let's get started.

In this lesson, you're going to use specific language to draw attention to data on a slide, and then explain the main points that is the takeaway from the chart or graph, and finally, to summarize its importance and relevance to your topic. Before we begin, remember that slides support your main ideas. Use graphs and charts only when necessary, don't overdo it. Keep them simple. Complicated charts with too much data on are difficult for you to explain and for the audience to see as you saw in the last lesson. It's really irritating to hear a presenter apologize, oh, I know you can't see this very well. If we can't see it, don't use it, or give it in a handout if it's important for the audience to have. Give your audience enough time to view the slide, and don't go into too much detail. Spend the appropriate amount of time for your audience to understand what the slide shows and how it's relevant to the main point of your presentation.

Now, let's look at some vocabulary for common visuals used in business to describe data. A table uses rows and columns to show data using text and numbers. Generally speaking, tables are not great to show in a presentation because they usually have too much information and it's difficult to read. It's better to show the information from a table in a different kind of visual. A line graph is a diagram that shows the relationship between two sets of numbers, for example, how something changed over time. The x-axis is the horizontal line of a graph. The y-axis is the vertical line. On the graph, we usually use a line to show changes. We begin with a solid line, and then to show more information, we use another line of a different color, like a red line, or we use a dotted line or a broken line. But in a presentation using slides, it's often difficult to see the difference between these lines.

A bar chart or a bar graph is sometimes easier to see on a slide because it uses larger visual elements to show information about data. There are many different kinds of charts, but these are the most common ones used in business. A bar chart or bar graph shows quantities in columns, usually different color columns. This is very helpful if you're showing several things at the same time. For example, how the use of mobile devices has increased over time compared to desktop or laptops. A pie chart is often used to show percentages. In marketing, a pie chart often shows market share or segment. One thing to be careful about is the key. The key explains what the colors in a chart represent. Make sure the key is large enough for people in the audience to read, or instead of a key, label the segments clearly.