Speeches of definition
In a definition speech, you must define the terms. You can define terms, system or theory.
Here are some examples
Defining a term
What is a smart card?
What is perjury?
What is bipolar disorder?
What is politically correct?
Defining a system or a theory
What is virtual reality?
What is futurism?
Defining similar and dissimilar terms or systems
What do Christians and Muslims have common
How the text and the online dictionary differ
Football or soccer main differences
Animals and human rights
Visible and invisible web