Creating a visualization means taking query results and making graphic representations of the data, such as graphs or charts. The visualizations tell your story, and your words will add the required context, which follows along with the expression that a picture is worth a thousand words. You don't want your audience to sit there reading or watching you read from dry slides of paragraphs or tables, describing your data in great detail. Of course, the detail can and should be available to those who want or need to see it, but your presentation should be mostly visualizations, along with some context, for your findings to shine through.