There are three different types of informative speeches. They are the speech of demonstration, speech of description and the speech of definition. Each one maintains a different specific purpose, but all three types have the general purpose of to inform.
Speech of Demonstration
The speech of demonstration is commonly referred to as the process or "how to" speech. It intends to teach the audience how to complete a task through step-by-step instruction. It generally uses a temporal (chronological) pattern as each "step" of the process takes the audience through a sequence of time.
If your speech topic is a process, your goal should be to help your audience understand it, or be able to perform it. In either instance, processes involve a predictable series of changes, phases, or steps.
- Bathe a dog
- Bake a cake
- Soil erosion
- Cell division
- Treating frostbite
- Training for a marathon
You will need presentation aids in order to make your meaning clear to your listeners. Even in cases where you don’t absolutely need a presentation aid, one might be useful. For instance, if your topic is how to train for a marathon, you might find it useful to have a visual aid that lists the steps involved in the training, and even the type of eating one might do to be in the best possible physical shape possible.
Organizing your facts is crucially important when discussing a process. Every stage of a process should be explained fully so that members of the audience could repeat what you told them after they leave the classroom.
Speech of Description
A descriptive speech is given to describe an object, person, place, or event. Depending on the topic of the speech, it can be laid out in a topical, spatial, temporal or chronological format.
The term “objects” encompasses many topics we might not ordinarily consider to be “things.” The following are some of these topics:
- Dream catchers
- Hubble telescope
- Spruce Goose
- Silicon chip
- Soy inks
- Cell phones
- Seattle’s Space Needle
- DDT insecticide
- Seattle’s Space Needle
You will find it necessary to narrow your topic about an object because, like any topic, you can’t say everything about it in a single speech. In most cases, there are choices about how to narrow the topic. Here are some specific purpose statements that reflect ways of narrowing a few of those topics:
- To inform the audience about what we’ve learned from the Hubble telescope
- To inform the audience about the evolution of the cell phone
- To describe the significance of the gigantic Spruce Goose, the wooden airplane that launched an airline
These specific purposes reflect a narrow, but interesting, approach to each topic. These purposes are precise, and they should help you maintain your focus on a narrow but deep slice of knowledge.
This category applies both to specific individuals and also to roles. The following are some of these topics:
- Dalai Lamas
- Tsar Nicholas II
- Modern midwives
- Mata Hari
- Catherine the Great
- Navajo code talkers
- Madame Curie
- Leopold Mozart
- The Hemlock Society
- Sonia Sotomayor
- Jack the Ripper
- Mahatma Gandhi
- Justice Thurgood Marshall
There is a great deal of information about each one of these examples. In order to narrow the topic or write a thesis statement, it’s important to recognize that your speech should not be a complete biography, or time line, of someone’s life. If you attempt to deliver a comprehensive report of every important event and accomplishment related to your subject, then nothing will seem any more important than anything else. To capture and hold your audience’s interest, you must narrow to a focus on a feature, event, achievement, or secret about your human topic aside from just providing background information.
Here are some purpose statements that reflect a process of narrowing:
- To inform the audience about the training program undergone by the first US astronauts to land on the moon
- To inform the audience about how a young Dalai Lama is identified
- To inform the audience about why Gandhi was regarded as a mahatma, or “great heart”
- To inform the audience about the extensive scientific qualifications of modern midwives
Without a limited purpose, you will find, with any of these topics, that there’s simply too much to say. Your purpose statement will be a strong decision- making tool about what to include in your speech.
An event can be something that occurred only once, or an event that is repeated:
- The Olympics
- The Iditarod Dogsled Race
- The Industrial Revolution
- The discovery of the smallpox vaccine
- The Bikini Atoll atomic bomb tests
- The Bay of Pigs
- The Super Bowl
- The Academy Awards
Again, we find that any of these topics must be carefully narrowed in order to build a coherent speech. Failure to do so will result in a shallow speech. Here are ways to narrow the purpose:
- To describe how the Industrial Revolution affected the lives of ordinary people
- To inform the audience about the purpose of the Iditarod dogsled race
There are many ways to approach any of these and other topics, but again, you must emphasize an important dimension of the event. Otherwise, you run the risk of producing a timeline in which the main point gets lost. In a speech about an event, you may use a chronological order, but if you choose to do so, you can’t include every detail. The following is an example:
Specific Purpose: To inform the audience about the purpose of the Iditarod dogsled race.
Thesis or Central Idea: The annual Iditarod commemorates the heroism of Balto, the sled dog that led a dog team carrying medicine 1150 miles to save Nome from an outbreak of diphtheria.
- Diphtheria broke out in a remote Alaskan town.
- Dogsleds were the only transportation for getting medicine.
- The Iditarod Trail was long, rugged, and under siege of severe weather. IV.Balto the dog knew where he was going, even when the musher did not.
- The annual race commemorates Balto’s heroism in saving the lives of the people of Nome.
In this example, you must explain the event. However, another way to approach the same event would describe it. The following is an example:
Specific Purpose: To describe the annual Iditarod Trail Sled Dog Race.
Thesis or Central Idea: It’s a long and dangerous race.
- The 1150-mile, ten- to seventeen-day race goes through wilderness with widely spaced checkpoints for rest, first aid, and getting fresh dogs.
- A musher, or dogsled driver, must be at least fourteen years old to endure the rigors of severe weather, exhaustion, and loneliness.
- A musher is responsible for his or her own food, food for twelve to sixteen dogs, and for making sure they don’t get lost.
- Reaching the end of the race without getting lost, even in last place, is considered honorable and heroic.
- The expense of participation is greater than the prize awarded to the winner.
By now you can see that there are various ways to approach a topic while avoiding an uninspiring timeline. In the example of the Iditarod race, you could alternatively frame it as an Alaskan tourism topic, or you could emphasize the enormous staff involved in first aid, search and rescue, dog care, trail maintenance, event coordination, financial management, and registration.
You’ve probably noticed that there are topics that could be appropriate in more than one category. For instance, the 1980 eruption of Mt. St. Helen’s could be legitimately handled as an event or as a process. If you approach the eruption as an event, most of the information you include will focus on human responses and the consequences on humans and the landscape. If you approach the eruption as a process, you will be using visual aids and explanations to describe geological changes before and during the eruption. You might also approach this topic from the viewpoint of a person whose life was affected by the eruption. This should remind you that there are many ways to approach most topics, and because of that, your narrowing choices and your purpose will be the important foundation determining the structure of your informative speech.
Speech of Definition
A speech of definition deals with explaining a concept or term. Generally, it is laid out in a topical, temporal or chronological format.
Concepts are abstract ideas that exist independent of whether they are observed or practiced. Concepts can include hypotheses and theories.
The glass ceiling
Here are a few examples of specific purposes developed from the examples:
- To explain why people in all cultures are ethnocentric
- To describe the Hindu concept of karma
- To distinguish the differences between the concepts of wellness and health
- To show the resources available in our local school system for children with autism
- To explain three of Dr. Stephen Suranovic’s seven categories of fairness
Here is one possible example of a way to develop one of these topics:
Specific Purpose: To explain why people in all cultures are ethnocentric.
Thesis (Central Idea): There are benefits to being ethnocentric.
- Ethnocentrism is the idea that one’s own culture is superior to others.
- Ethnocentrism strongly contributes to positive group identity.
- Ethnocentrism facilitates the coordination of social activity.
- Ethnocentrism contributes to a sense of safety within a group.
- Ethnocentrism becomes harmful when it creates barriers.