The following figure gives a quick summary of the process from data gathering to presentation of results.
Experiments (data gathering research) in the laboratory generally produce mountains of data. A critical part of the presentation process (also part of the research process) is to take that mountain of data, figure out what is important and decisive, and understand the proper context for that data (context is symbolized by the layout of the pages on the grass). You cannot proceed to the presentation until you have figured out what small portion of your data is important and explanatory.
The key point is that a slide presentation is not a "data dump." It concisely summarizes the thematic lessons learned from the research.