Standard presentation requirements state that the size of the screen should be one-sixth the depth of the room. So for a room 120 feet deep, a screen that's 20 feet wide is necessary. Usually, presentation software takes distance into account. Often, defaults are set recommending font sizes of 30 and 40. Such software also offers preset color combinations for text and backgrounds that are visibly pleasing and are effective at longer distances.
Most presentation software includes graphics and images that can be used as part of a presentation.
But Web pages and other documents on computer monitors are another story altogether. They are designed to be viewed by one person at a distance of less than 20 inches. Ironically, some presenters fail to take this into account because even during the pr esentation they are staring at a 15-inch monitor or small laptop screen. Unfortunately, the audience gets seasick while the mouse glides swiftly across the screen or while a page goes scrolling by in a blur. Most trainers learn, through experience, to slo w down, to tell the audience what they are about to do, and to repeat movements as needed.