Notes are short written records made while reading.
Purpose of notes:
Notes are prepared for future references. The purpose of notes is to avoid going through the trouble of reading the text again and read what is relevant. This saves time, energy, brings clarity in thinking, reduces load on the mind and is easy to remember.
Studying and Examination :
A study is carried out due to interest or necessity. Examination is the place where one's study is put to test. A good performance at examination requires revision. Depending on one's preparation and one's commitment to the exam revision is carried out once or more than once. The Civil Services exam requires revision quite a number of times. None tracks the number of times of their revision but it usually lies between 6-10 times. Sometimes even more. The mode of revision also varies. The time ticks constantly and as the exam date appears one is left with lesser and lesser time to revise. Initially a detailed revision would take about a month per optional. Then one would have to revise the whole subject within a week. Later in two days and just before exam within a day. Thus the notes that one prepares must help recall the concepts and related items in less time.
Unique-ness of Notes:
Everyone's notes are unique. This is because of the simple reason that every has a different writing style. Each has his/her own creative ways to convince the examiner that they are well versed with their concepts. The notes are reflection of ones writing style and thought process. So, one person's notes may be the best for him/her while it may seem utter useless to others. The notes one prepares are to help recall the concepts hence, one must write in ways how faster, easier and precise do they recall.
Preparing the Notes:
Studying a text in general requires about three readings atleast. First to read all chapters individually. Second to be able to connect various chapters and their concepts. Third to understand the essence of the book. It can take more readings depending on the person, the context or situation and many other things. It is only at the third or fourth reading that the meanings mentioned in a book become clear. This is when the notes are to be prepared. In the meantime, practicing tests reveal what is needed in the answer to call it a good answer. Some particular sentences, certain vocabulary, thinkers/scholars related to the subject, examples/illustration etc. The notes written at third or fourth reading automatically will include tha aforementioned aspects. A good amount of reading is quite necessary to make a contributing notes.
Notes as a continuous activity:
No notes is complete in itself for the fundamental fact that there is always something to learn. No matter how much expertise one gains in subject there will always be a new thing one learns every time. Secondly, many books might be referred during a study. Contents from such sources can be consolidated in the notes. Sometimes one comes across items in newspapers, TV, internet or just during a discussion. Those things can enrich the notes.