A catchword is a word that is made up of the first letters of several words you want to remember. A catch phrase or sentence, on the other hand, is one which the first letters of each word in the phrase correspond to the first letter of an item to be remembered. Mnemonics rely on deliberately created, even contrived, associations. Many lists of things can be so transformed into catchy mnemonics with a little effort. What does help us to remember large amounts of material is hierarchical organization.
Hierarchical organization requires active learning.
It may be likened to the development of a structural framework in which the more important or general information is listed and then less important or specific information is listed below in order of decreasing generality. A good example is the classification system utilized in biology. The hierarchical organization or arrangement of information is one of the most basic and strongest techniques for developing the long-term memory because it involves weaving information into a web. And this weaving of information forces you to become an active learner, looking for your own organizational patterns. New information can not only be inserted into the web, but becomes caught and held like a fly in a spider's web.