The vector clipart library "Presentation" design elements contains 45 symbols you can use to design your presentation slides and illustrations using the ConceptDraw PRO diagramming and vector drawing software.
"Although some think of presentations in a business meeting context, there are often occasions when that is not the case. For example, a non-profit organization presents the need for a capital fund-raising campaign to benefit the victims of a recent tragedy; a school district superintendent presents a program to parents about the introduction of foreign-language instruction in the elementary schools;an artist demonstrates decorative painting techniques to a group of interior designers; a horticulturist shows garden club members or homeowners how they might use native plants in the suburban landscape; a police officer addresses a neighborhood association about initiating a safety program. ...
A study done by Wharton School Of Business showed that the use of visuals reduced meeting times by 28 percent. Another study found that audiences believe presenters who use visuals are more professional and credible than presenters who merely speak. Other research indicates that meetings and presentations reinforced with visuals help participants reach decisions and consensus more quickly." [Presentation. Wikipedia]
The clip art example "Design elements - Presentation symbols" is included in the Presentation Clipart solution from the Illustration area of ConceptDraw Solution Park.