When you make an informative speech you are explaining something to your audience. An informative speech can be a description of an object, a demonstration of a process, a report about an event, or an explanation of a concept (Menke), but make sure that the speech is also useful for your audience because it is relevant and it provides "a thoughtful or unique insight on the topic" (Phillips, n.d.).
Here is more from Terry O'brien Menke on what an informative speech is:
The purpose of the explanatory speech is to create understanding. Topics for explanatory speeches come from asking, “Why?” or “What does that mean?” Your purpose in this assignment is to identify the primary difficulty your audience faces in accepting your thesis, and then shaping your speech to overcome that difficulty. The informative value of a speech is measured by how much new and important information or understanding it provides the audience.
The following questions might be new information for a public speaking class:
1. Why do people yawn?
2. Why are water towers shaped like giant mushrooms?
3. How does nuclear fusion work?
4. Why are some people resilient?
5. What is totalitarianism?
6. What is a carabineer?
7. What shapes do snowflakes come in?
To determine the appropriateness of your topic for the informative speech, ask yourself the following questions:
1. Is my topic challenging enough to merit an informative speech?
2. What do my listeners already know about my topic?
3. What more do they need to know?
4. Do I have sufficient understanding of my topic to help others understand it better?
Here are competencies that you should develop as your practice delivering speeches (from Terry O'brien Menke)
Competencies
1. To choose and narrow a topic appropriate to the audience and occasion
2. To formulate and communicate a clear specific purpose/thesis in a manner appropriate for the audience and occasion
3. To develop ideas