

What are presentation and presentation skills?
The speakers have to have perfect communication skills and presentation methods to convey their knowledge to others.
Read this article: Public speaking and presentation
By presentation methods I mean they have to choose an attractive topic, exciting content and they must organize their content and use some creativity in it like using stories and examples.
By communication skills, I mean the ability to talk, use language and body language and change the mimic of the face at the right time.

Speakers need to know how to walk on the stage and how to talk to have a fantastic presentation
But the presentation is a professional work to do. People who perform a speech should at least know something about communication skills.
The speakers must know how to present during the time they have and use technology (especially PowerPoint), notes and handouts while they do.
More info about PowerPoint and a introducing one of the best references: Slide:ology book
Buy this book ⇒ slide:ology book by Nancy Duarte
Speakers know where should they stand and how to stand on the stage. With which voice they have to talk and how to use their body language to make an impression. Speakers don’t come on the stage to do an unnecessary job. They have to transfer what they’re thinking and what they have researched to others and teach something to the audience, so they have to be careful. They need to be perfect so that the audience doesn’t get tired and bored and learn something at the same time.
All speakers have their unique presentation style. They have to choose a topic and perform based on that particular subject.
Different kinds of presentations
Presentations have different kinds, such as:

One of the presentation kinds is the academic lectures.
1- Academic and scientific lectures
2- Improvisational speeches (like in ceremonies, weddings, and funerals)
3- Political presentations(with a specific purpose which the audience may not accompany the speaker!)
And many others.
A presentation is a professional ability and the combination of art and knowledge. All people can be (and must be) a fantastic speaker by practicing.
In this article, you can use the links to read other articles about presentations.