What's the difference between molecular biology and comparative biochemistry?

The difference between molecular biology and comparative biochemistry are:

Molecular biology is the branch of biology in which we study about the chemical composition and structure of atoms of macromolecules such as protein and nucleic acid which are the main component of life forming substances, while Comparative biochemistry is a branch of chemistry in which we study the similarities and differences between different biological processes that occurs in different living organisms.

The difference between biochemistry and molecular biology is that biochemists study molecules separately from the rest of the organism, whereas molecular biologists look at the interactions of molecules. Molecular cell biology dates back to the 1930's, when Warren Weaver coined the term molecular biology.