One of the main problem MXTNote tries to solve is this: Sometimes we need to write a summary about a topic, we study the topic from a few articles, and there are important formula/diagrams from the articles. There are two common ways to take notes, one is to annotate the document PDF, if the PDF has dense text, there are usually not much room for notes, also its not easy to keep the notes which belongs to the same topic toghether, another way is to write your notes as a separate document and copy the content from the original document, but then usually we might want to review the material around the part we copied, MXTNote make it easy to copy the clips from the original document, and at the same time keep a link between your notebook and the original document, so you can quickly jump from one side to the other.