The main ways these methods of note taking formats are different is the obvious, the way they are set up. Outlining deals with the main ideas using roman numerals (I, II, III) and sub topics using capital letters of the alphabet (A, B, C). Mind mapping consists of the main idea(s) being circled and then sub topics for the main idea branching off from that. The Cornell method divides a paper into 3 separate areas. You draw a line in the middle of the paper (horizontally). Then on only the top portion you draw a vertical line down, the left side is usually smaller than the right side, so do not draw it directly down the middle. The smaller portion on the top is for the main idea and the right side is for important facts and ideas about the main idea. The bottom portion of the paper is then used for a summary of the notes.
The way that these note taking styles are similar is because they all focus on stating the main idea and the sub topics. All of these are great methods for writing a paper because it helps break down what exactly you intend to write about.
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