When you have information or ideas to share with an audience, you must do some kind of presentation. You could just talk and wave your hands around a lot. But, most of us find it helpful to to see your points up on a screen from slides or transparencies. Printed handout sheets to take home and to make notes on during your presentation are also very helpful. All of these supplements to your words can be created using presentation software  (also called presentation graphics).

In English: http://www.jegsworks.com/Lessons/presentations/index.html

In Spanish: http://www.jegsworks.com/Lessons-sp/presentations/index.html