A mnemonic (pronounced nee-MON-ik) is a memory aid you can use to improve your long term recollection of a topic. Mnemonic devices can help you remember information that you initially may have thought was difficult to remember. Rules, names, sequences and concepts in many subjects can be memorized easily and efficiently with the use of mnemonic devices. In this article I will list a few subjects and at least one mnemonic for each subject.
Biology
The taxonomy (full biological classification) of human beings is given as:

Animalia, Chordata, Mammalia, Primate, Hominidae, Homo sapiens.

A mnemonic to help you remember the above information is:

“All Cool Men Prefer Having Heavy Sideburns”

If you’re not convinced that all cool men prefer having heavy sideburns but you’re a fan of the sport of swimming, then try the following mnemonic instead:

“Amanda Called Michael Phelps Hoping He’d Stop”

Psychology
Some People Can Fly! Explanation: to remember Piaget’s stages of cognitive development, in order:
Sensorimotor, Pre-operational, Concrete Operational, Formal Operational.
Chemistry
Students studying Chemistry often mix up what happens with oxidation and reduction reactions. Often, the term redox is used to indicate that a reaction has both a reduction half and an oxidation half. Here is a mnemonic that can help you remember the differences.
LEO GER
The Loss of Electrons is Oxidation; the Gain of Electrons is Reduction.
If you want to remember all the diatomic elements Hydrogen, Oxygen, Nitrogen, Fluorine, Chlorine, Bromine and Iodine. Then use the following mnemonic:
I Bring Clay For Our New House
Physics
The order of increasing frequency or decreasing wavelength of electromagnetic waves are:
Radio waves, Microwaves, Infrared, Visible light, Ultraviolet, X-rays, Gamma rays. Here are 2 mnemonics fixated on x-ray guns that will help you remember the list of electromagnetic waves.

Roman Men Invented Very Unusual X-Ray Guns
or
Raging Martians Invaded Venus Using X-ray Guns

Calculus

This important branch of Mathematics deals with the slope or rate of change of functions, otherwise known as derivatives. To find the derivative of a function divided by a function such as f(x)/g(x) we use what is called the quotient rule. It looks like this:

gf’- fg’/g²

To remember the steps of the quotient rule, follow this mnemonic (that could be turned into jingle):

“Low dee High, high dee low. Over low squared.”

As you can see, with a little creativity, you could come up mnemonics to help you remember many different kinds of information and important concepts in the subjects you are studying. They many kinds of mnemonics in use currently are limited only by the imagination. Create and use mnemonics and begin to retain important information that you need to recall for quizzes, midterms, exams…and for life!