Hand gestures when you present

Non-verbal gestures are classified as emblems and illustrators.

• Emblems are gestures that stand in for words, such as a "thumbs up" gesture and the "shhh" gesture. We can quickly know what they mean without much context.
• Illustrators are gestures that accompany words. They are intimately related to the moment with speech, phrasing, content, voice, and so on.

When you give a presentation, the hand gestures you are using are illustrators. Your hand motions combined with your speech are part of the communication process.