In general, a Scientific Law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a Scientific Theory. A law is an observation used for prediction while theory is an explanation. A Law states what happens while a theory is an explanation of why and how things happen.Example: Observing an apple fall from a branch of an apple tree to the ground. The observation of this phenomena can be called the Law of Gravity. The law of gravity states that every time you drop an apple, it will fall to the ground also paving a path to the prediction that every time an object is dropped, it would fall to the ground. The theory of general relativity is the explanation as to why the apple falls to the ground. A theory of gravitation is a description of the long range forces that electrically neutral bodies exert on one another because of their matter content. The article Scientific Laws and Theories present the list of the Discoveries of Scientific Laws and Theories and their Inventors.
Laws and Theories are primarily based on basic elements of the scientific method: generation of hypothesis, testing that premise, finding (or not finding) empirical evidence and arriving at conclusion for further predictions. Scientific Laws describe a phenomena of Universe based on repeated experimental observations. Scientific laws are primarily tested based on their ability to predict the results of future experiments. Laws are strongly supported by empirical evidence and are developed from facts and can be reduced to mathematical equations thus paving a path for predictions.
Formulation of new theories and support from the new theories heightens the application of laws in the new arenas, thus creating a path for superior predictions.

Scientific Laws describe what happens while Scientific Theories explain why the phenomena occurs. Laws reflect scientific knowledge that experiments have repeatedly verified. Multiple theories may strive to supply the best explanation of a new scientific law. The strength of a scientific theory is related to the diversity of phenomena it can explain. Laws and Theories are always a work in progress striving to explain and predict different possible occurrences. Below table lists some of the important Scientific Laws and Theories.