Your notes include all the facts and opinions you need to develop your thesis.
Take your notes on cards or half sheets of paper, and put a subtopic on each card. You should also identify the source of your information. Every time you change subtopic or source, start a new card. Notes should consist of phrases, unless you are directly citing the source, in which case you should use quotation marks and note the page number. You may not know at the time of note-taking whether you will quote this information directly or paraphrase it, but it is wise to indicate all material that is copied word for word. All pictorial material should be captioned and labeled as to source and any other material, e.g., sound, video, etc., should also be given proper documentation.
Here is an excerpt from an encyclopedia article about earthquakes:
Bolt, B. "Earthquakes." Encyclopaedia Britannica. 1988 ed.: 611.
Principal types of seismic waves. Seismic waves generated by an earthquake source are commonly classified into three main types. The first two, the P and S waves, are propagated within the Earth, while the third, consisting of Love and Rayleigh waves, is propagated along its surface (Figure 1). The existence of these types of seismic waves was predicted during the 19th century, and modern investigators have found that there is a close correspondence between such theoretical calculations and seismographic measurements of the waves.
The P (or primary) waves travel through the body of the Earth at the highest speeds. They are longitudinal waves that can be transmitted by both solid and liquid materials in the Earth's interior. With P waves, the particles of the medium vibrate in a manner similar to sound waves, and the transmitting rocks are alternately compressed and expanded. The other type of body wave, the S (or secondary) wave, travels only through solid material within the Earth. With S waves, the particle motion is transverse to the direction of travel and involves the shearing of the transmitting rock.
Here is a sample note card using that information:
Earthquakes - Waves Bolt 611
Kinds: body waves travel through earth--2 kinds
P - primary: longitudinal (particles travel in direction of wave)
move at highest speeds
travel thru earth's interior (both solid and liquid materials)
S - secondary: transverse (particles travel across the direction of the wave)
travel only thru solid materials
Other kinds - Love and Rayleigh: travel only along surface
Illus.: Ground motion of 4 main types of waves
Scan for major ideas and keywords to identify useful information. Look at: headings and subheadings, introductory and concluding paragraphs, illustrations and charts.