Types of Informative Speeches

In the last section we examined how informative speakers need to be objective, credible, knowledgeable, and how they need to make the topic relevant to their audience. This section discusses the four primary types of informative speeches. These include definitional speeches, descriptive speeches, explanatory speeches, and demonstration speeches.

Definitional Speeches

In definitional speeches the speaker attempts to set forth the meaning of concepts, theories, philosophies, or issues that may be unfamiliar to the audience. In these types of speeches, speakers may begin by giving the historical derivation, classification, or synonyms of terms or the background of the subject. In a speech on “How to identify a sociopath,” the speaker may answer these questions: Where did the word ‘sociopath’ come from? What is a sociopath? How many sociopaths are there in the population? What are the symptoms? Carefully define your terminology to give shape to things the audience cannot directly sense. Describing the essential attributes of one concept compared to another (as through use of analogies) can increase understanding as well. For a speech on “Elderly Abuse,” the speaker may compare this type of abuse to child or spousal abuse for contrast.

Regardless of the listeners’ level of knowledge about the subject, it is very important in these types of speeches to show the relevance of the topic to their lives. Often the topics discussed in definitional speeches are abstract—distanced from reality. So provide explicit, real-life examples and applications of the subject matter. If you were going to give a speech about civil rights, you would need to go beyond commonly held meanings and show the topic in a new light. In this type of speech, the speaker points out the unique and distinguishing properties or boundaries of a concept in a particular context (Rinehart, 2002). The meaning of “civil rights” has changed significantly over time. What does it mean today compared to the 1960s? How will knowing this distinction help audience members? What are some specific incidents involving civil rights issues in current news? What changes in civil rights legislation might listeners see in their lifetimes?

Sample Definitional Speech Outline

Title: “Life is suffering,” and Other Buddhist Teachings (Thompson, 1999)

Specific Purpose: At the end of my speech, my audience will understand the Four Noble Truths and the Eightfold Path in Buddhism

Central Idea: Regardless of your religious beliefs, Buddhist philosophy teaches a number of useful lessons you can apply to your own life.

  1. Four Noble Truths
    1. All life involves dukkha (suffering)
    2. Suffering is caused by tanha (longing for things to be other than they are)
    3. If this longing stops (nirodha), suffering will cease
    4. The way to eliminate longing is to follow the Eightfold Path
  2. The Noble Eightfold Path (the Middle Way)
    1. Right view
    2. Right intention
    3. Right speech
    4. Right action
    5. Right livelihood
    6. Right effort
    7. Right mindfulness
    8. Right contemplation

Descriptive Speeches


White domed structure with four surrounding pillars against a blue skyThe purpose of descriptive speeches is to provide a detailed, vivid, word picture of a person, animal, place, or object. Audiences should carry away in their minds a clear vision of the subject (Osborn & Osborn, 1991). Consider this description of the Taj Mahal in Agra, India by Steve Cassidy (edited for length).

To gaze in wonder at that magnificent dome and elegant gardens will be a moment that you remember for the rest of your life. The Taj Mahal just takes your breath away. What is immediately striking is its graceful symmetry—geometric lines run through formal gardens ending in a white marble platform. Atop this platform is great white bulbous dome complemented by four towering minarets in each corner. The whole image shimmers in a reflecting pool flanked by beautiful gardens—the effect is magical. The first stretch by the reflecting pool is where most people pose for their photos. But we were impressed by the fresh, green gardens. As you approach through the gardens two mosques come into view flanking the Taj—both exquisitely carved and built of red sandstone.

In the descriptive speech, determine the characteristics, features, functions, or fine points of the topic. What makes the person unique? How did the person make you feel? What adjectives apply to the subject? What kind of material is the object made from? What shape is it? What color is it? What does it smell like? Is it part of a larger system? Can it be seen by the naked eye? What is its geography or location in space? How has it changed or evolved over time? How does it compare to a similar object? When preparing for the speech, try to think of ways to appeal to as many of the senses as possible. As an example, in a speech about different types of curried dishes, you could probably verbally describe the difference between yellow, red, and green curry, but the speech will have more impact if the audience can see, smell, and taste samples.

Sample Descriptive Speech Outline

An enormous stone carved into a human headTitle: Easter Island: The Navel of the World (Fischer, 2006)

Specific Purpose: At the end of my speech, my audience will be able to visualize some of the main attractions on Easter Island.

Central Idea: Easter Island hosts a number of ancient, mysterious, and beautiful attractions that make it an ideal vacation destination.

  1. Stone Giants—“Moai”
    1. Average 13 feet high; 14 tons
    2. Play sacred role for Rapa Nui (native inhabitants)
    3. Central Ahu ceremonial sites
  2. Coastline activities
    1. Beaches
    2. Snorkeling & Scuba
    3. Surfing
  3. Rano Kau Chilean National Park
    1. Giant crater
    2. Sheer cliffs to ocean
    3. Sea birds
Be able to describe anything visual, such as a street scene, in words that convey your meaning. ~ Marilyn vos Savant

Explanatory Speeches

An explanatory speech (also known as a briefing) is similar to the descriptive speech in that they both share the function of clarifying the topic. But explanatory speeches focus on reports of current and historical events, customs, transformations, inventions, policies, outcomes, and options. Whereas descriptive speeches attempt to paint a picture with words so that audiences can vicariously experience it, explanatory speeches focus on the how or why of a subject and its consequences. Thus, a speaker might give a descriptive speech on the daily life of Marie Antoinette, or an explanatory speech on how she came to her death. Recall that definitional speeches focus on delineating concepts or issues. In this case, a speaker might give a definitional speech about the Emergency Economic Stabilization Act of 2008, or an explanatory speech on why the financial bailout was necessary for U.S. financial stability.

If a manager wanted to inform employees about a new workplace internet use policy, s/he might cover questions like: Why was a policy implemented? How will it help? What happens if people do not follow established policies? Explanatory speeches are less concerned with appealing to the senses than connecting the topic to a series of related other subjects to enhance a deep understanding (McKerrow, Gronbeck, Ehninger, & Monroe, 2000). For example, to explain the custom of the Thai wai greeting (hands pressed together as in prayer), you also need to explain how it originated to show one had no weapons, and the ways it is tied to religion, gender, age, and status.

Sample Explanatory Speech Outline

Title: Giant Waves, Death, and Devastation: The 2004 Indian Ocean Tsunami (National Geographic, 2006)

Specific Purpose: At the end of my speech, my audience will be aware of the nature of the 2004 Tsunami and the destruction it caused.

Central Idea: The 2004 Asian Tsunami was one of the worst natural disasters in human history in terms of magnitude, loss of human life, and enduring impact.

  1. Geological event
    1. Earthquake epicenter and magnitude
    2. Tsunami forms (waves reach up to 100 feet)
    3. Tsunami strikes land of various countries with no warning
  2. Human casualties reach almost 230,000—top 10 of all natural disasters
    1. The countries and people involved
    2. Loss of food, water, hospitals, housing, electricity, and plumbing
    3. Threat of disease
  3. Ongoing effects
    1. Environmental destruction
    2. Economic devastation
    3. Psychological trauma
I hear and I forget. I see and I remember. I do and I understand. – Confucious

Demonstration Speeches

The most practical of all informative speeches, a demonstration speech shows listeners how some process is accomplished or how to perform it themselves. The focus is on a chronological explanation of some process (how potato chips are made), procedure (how to fight fires on a submarine), application (how to use the calendar function in Outlook), or course of action (how court cases proceed to Supreme Court status). Speakers might focus on processes that have a series of steps with a specific beginning and end (how to sell a home by yourself) or the process may be continuous (how to maintain the hard drive on your computer to prevent crashes). Demonstration speeches can be challenging to write due to the fact that the process may involve several objects, a set of tools, materials, or a number of related relationships or events (Rinehart, 2002). Nevertheless, these types of speeches provide the greatest opportunity for audience members to get involved or apply the information later.

When preparing this speech, remember first to keep the safety of the audience in mind. One speaker severely burned his professor when he accidently spilled hot oil from a wok on her. Another student nearly took the heads off listeners when he was demonstrating how to swing a baseball bat. Keep in mind also that you may need to bring in examples or pictures of completed steps in order to make efficient use of your time. Just think of the way that cooking demonstrations are done on TV—the ingredients are premeasured, the food is premixed, and the mixture magically goes from uncooked to cooked in a matter of seconds. Finally, if you are having your audience participate during your presentation (making an origami sculpture), know what their knowledge level is so that you don’t make them feel unintelligent if they are not successful. Practice your speech with friends who know nothing about the topic to gauge if listeners can do what you are asking them to do in the time allotted.

Sample Demonstration Speech Outline

Title: How to Survive if You Get Stranded in the Wilderness (U.S. Department of Defense, 2006).

Specific Purpose: At the end of my speech my audience will understand what to do if they unexpectedly become stranded in the wilderness.

Central Idea: You can greatly improve your ability to stay alive and safe in the wilderness by learning a few simple survival techniques.

  1. Size up the situation
    1. Size up the surroundings
    2. Size up your physical and mental states
    3. Size up your equipment (handout “What to Include in a Survival Kit”)
  2. Survival Basics
    1. Obtaining water
    2. Acquiring food
    3. Building a fire
    4. Locating shelter
  3. Finding help
    1. Call or signal rescue personnel
    2. Wilderness navigation
    3. Leaving “bread crumb” trail