What is the difference between science and pseudoscience?

Major difference between science and pseudoscience is facts behind their theories.  

Explanation:

The major difference between science and pseudoscience is facts behind their theories.  

In case of science the facts or theories are well established and proven again and again to explain various natural principles. While pseudoscience is based on beliefs rather than facts. For example – existence of planets in the solar system is a science but  impacts of these planets on an individual's future life as established by astrology is a pseudoscience.

Life and death are a scientific concept but existence of spirits is a  pseudoscience.

a polymer is a chainlike molecule made up of small molecular units. these small molecular units are called monomers. monomers of polymer can be joined together either naturally or synthetically.