When you summarize information, you explain the most important parts of a source text in your own words. You typically summarize something to make it shorter. The page number is not required in the in-text citation for a summary. See the "Using Sources: In-text Citations" section of the textbook for more information on how to cite summaries.
An effective summary—
- explains the most important parts of the original.
- is written in your own words.
- keeps the original meaning.
- does not merely cut and copy from the original.
- is shorter than the original.
Below is an excerpt from a website article that describes barometers. This example will be used on the next several pages to illustrate how to write a summary.
Original Source
"A barometer is a scientific instrument used to measure atmospheric pressure, also called barometric pressure. The atmosphere is the layers of air wrapped around the Earth. That air has a weight and presses against everything it touches as gravity pulls it to Earth. Barometers measure this pressure.
Atmospheric pressure is an indicator of weather. Changes in the atmosphere, including changes in air pressure, affect the weather. Meteorologists use barometers to predict short-term changes in the weather."
Example Summary
Because changes in atmospheric pressure are related to the weather, meteorologists can measure atmospheric pressure with a barometer to predict changes in the weather (Turgeon, 2014).
Here are some simple steps you can follow in order to create a summary:
- Determine your purpose.
- Read or listen to what you will summarize.
- Make a list of the main points.
- Write the summary.
- Compare the summary to the original.
Determine your purpose
The purpose of your summary will help you determine which details you should include. Compare the example summaries below. The first summary focuses on how barometers predict weather. The second summary focuses on what barometers are.
Example Source
"A barometer is a scientific instrument used to measure atmospheric pressure, also called barometric pressure. The atmosphere is the layers of air wrapped around the Earth. That air has a weight and presses against everything it touches as gravity pulls it to Earth. Barometers measure this pressure.
Atmospheric pressure is an indicator of weather. Changes in the atmosphere, including changes in air pressure, affect the weather. Meteorologists use barometers to predict short-term changes in the weather."
http://www.nationalgeographic.org/encyclopedia/barometer/
Example: Summary 1
Because changes in atmospheric pressure are related to the weather, meteorologists can predict the weather by measuring atmospheric pressure with a barometer (Turgeon, 2014).
Example: Summary 2
Meteorologists use a special tool to measure atmospheric pressure called a barometer, and this tool allows them to predict the weather (Turgeon, 2014).
Read/listen
Read or listen carefully so you understand the source well enough to summarize it.
Make a list
As you read/listen, pay attention to the main ideas and major details of the source material. You should make a list of these main points. Compare the example paragraph and the example list below.
| Example: Paragraphs | Example: List |
A barometer is a scientific instrument used to measure atmospheric pressure, also called barometric pressure. The atmosphere is the layers of air wrapped around the Earth. The air has a weight and presses against everything it touches as gravity pulls it to Earth. Barometers can measure this pressure. Atmospheric pressure is an indicator of weather. Changes in the atmosphere, including changes in air pressure, affect the weather. Meteorologists use barometers to predict short-term changes in the weather. | -Barometers measure atmospheric pressure. -Atmospheric pressure is related to weather. -Meteorologists predict the weather with barometers. |
Write the summary
Without looking at/listening to the original, use your list to write your summary. Again, it is important to focus on the ideas. Use your own words to write your summary.
| Example: List | Example Summary |
-Barometers measure atmospheric pressure. -Atmospheric pressure is related to weather. -Meteorologists predict the weather with barometers. | Because changes in atmospheric pressure are related to the weather, meteorologists can predict the weather by measuring atmospheric pressure with a barometer (Turgeon, 2014). |
Notice how the items on the list are not just copied and pasted together into one big sentence. The ideas are connected together carefully. The order is changed a little and some of the ideas are condensed. There are different synonyms used and there are new sentence structures. For example:
Atmospheric pressure is related to weather --> changes in atmospheric pressure are related to the weather
Compare to the original
After you write your summary, you should compare it to the original. Make sure that the ideas have not been changed, but that the words/syntax are distinct. Make revisions as necessary.
Example: Paragraphs
"A barometer is a scientific instrument used to measure atmospheric pressure, also called barometric pressure. The atmosphere is the layers of air wrapped around the Earth. The air has a weight and presses against everything it touches as gravity pulls it to Earth. Barometers can measure this pressure.
Atmospheric pressure is an indicator of weather. Changes in the atmosphere, including changes in air pressure, affect the weather. Meteorologists use barometers to predict short-term changes in the weather."
Example: Summary
Because changes in atmospheric pressure are related to the weather, meteorologists can predict the weather by measuring atmospheric pressure with a barometer (Turgeon, 2014).
Exercises
Exercise 1: Evaluate Summaries
Evaluate the summaries. Which summary is most effective? Identify features of the ineffective summaries that make them ineffective.
Original:
"A rapid drop in atmospheric pressure means that a low-pressure system is arriving. Low pressure means that there isn't enough force, or pressure, to push clouds or storms away. Low-pressure systems are associated with cloudy, rainy, or windy weather. A rapid increase in atmospheric pressure pushes that cloudy and rainy weather out, clearing the skies and bringing in cool, dry air" (Turgeon, 2014, para. 3).
- Atmospheric pressure changes frequently, thus causing the weather to change with it in dramatic ways (Turgeon, 2014).
- Cloudy, rainy, or windy weather are often associated with a decrease in atmospheric pressure, whereas clear skies usually follow greater atmospheric pressure (Turgeon, 2014).
- A rapid fall in atmospheric pressure means that a low-pressure system is arriving and low-pressure systems are associated with cloudy, rainy, or windy weather; a rapid increase in atmospheric pressure means the skies will be clear and bring in cool, dry air (Turgeon, 2014).
- Higher air pressure is related to bad weather while low pressure is related to good weather (Turgeon, 2014).
Exercise 2: Revise a summary
Revise the summary.
Original:
"A species' camouflage depends on several factors. The physical characteristics of the organism are important. Animals with fur rely on different camouflage tactics than those with feathers or scales, for instance. Feathers and scales can be shed and changed fairly regularly and quickly. Fur, on the other hand, can take weeks or even months to grow in. Animals with fur are more often camouflaged by season. The arctic fox, for example, has a white coat in the winter, while its summer coat is brown" (McDaniel, Sprout, Boudreau, & Turgeon, 2011, para. 2).
Summary:
A species' camouflage depends on several things, and one very important thing is the physical characteristics of the organism because there are different camouflage tactics the animals use depending on the different characteristics they have; for example, feathers and scales can be changed quickly, but fur takes a long time to grow, so animals who use fur to camouflage change according to the season, like the arctic fox (McDaniel, Sprout, Boudreau, & Turgeon, 2011).
Exercise 3: Write a summary
Use the original quote to create a summary.
Original:
"A barometer measures atmospheric pressure in units of measurement called the average pressure at sea level at a temperature of 15 degrees Celsius (59 degrees Fahrenheit). The number of atmospheres drops as altitude increases because the density of air is lower and exerts less pressure. As altitude decreases, the density of air increases, as does the number of atmospheres" (Turgeon, 2014, para. 4-5).
Original:
"Camouflage, also called cryptic coloration, is a defense or tactic that organisms use to disguise their appearance, usually to blend in with their surroundings. Organisms use camouflage to mask their location, identity, and movement. This allows prey to avoid predators, and for predators to sneak up on prey" (McDaniel, Sprout, Boudreau, & Turgeon, 2011, para. 1).
Exercise 4: Write a summary
The following paragraphs come from a longer article. Summarize all of the paragraphs in one paragraph or less.
Original:
"Background matching is perhaps the most common camouflage tactic. In background matching, a species conceals itself by resembling its surroundings in coloration, form, or movement. In its simplest form, animals such as deer and squirrels resemble the "earth tones" of their surroundings. Fish such as flounder almost exactly match their speckled seafloor habitats.
"More complex forms of background matching include the camouflage of the walking stick and walking leaf. These two insects, both native to southeast Asia, look and act like their namesakes. Patterns on the edge of the walking leaf’s body resemble bite marks left by caterpillars in leaves. The insect even sways from side to side as it walks, to better mimic the swaying of a leaf in the breeze" (McDaniel, Sprout, Boudreau, & Turgeon, 2011, para. 6-7).
"Countershading is a form of camouflage in which the top of an animal’s body is darker in color, while its underside is lighter. Sharks use countershading. When seen from above, they blend in with the darker ocean water below. This makes it difficult for fishermen—and swimmers—to see them. When seen from below, they blend in with lighter surface water. This helps them hunt because prey species below may not see a shark until it's too late.
"Countershading also helps because it changes the way shadows are created. Sunlight illuminates the top of an animal's body, casting its belly in shadow. When an animal is all one color, it will create a uniform shadow that makes the animal's shape easier to see. In countershading, however, the animal is darker where the sun would normally illuminate it, and lighter where it would normally be in shadow. This distorts the shadow and makes it harder for predators to see the animal's true shape" (McDaniel, Sprout, Boudreau, & Turgeon, 2011, para. 11-12).