How is a scientific law different from a scientific theory? This is a fundamental question which arises across disciplines.
A scientific law refers to a generalization (e.g., Kepler's Laws of Planetary Motion), whereas a scientific theory refers to a specific explanation which attempts to describe a particular phenomena (e.g., Big Bang Theory). Scientific laws are empirically based and are not intended explain why a particular phenomena occurs. They can often be reduced to a collection of mathematical expressions which are relevant under specific conditions. During an investigation, data is collected or observations are made in an effort to identify discernible patterns which may then be used to make generalizations. Thus, scientific laws arise as a result of an inductive process. A scientific theory attempts to piece together relevant laws in a rationale manner in an effort to create an explanation which attempts to describe why a phenomena occurs using a variety of scientific principles.