What is the difference between a preliminary literature review and a critical literature review?

Answer:

Difference:-

Preliminary literature review:

It makes the better identification of the literature that supports and ensures the topic is valid. The preliminary literature review concentrates on the areas that need to take support from the new research and offer researchers to analyze and produce something effective from past research in the context that is related to the present problematic areas of the research.     

Critical literature review:

A critical literature review is a type to analyze and evaluate the different levels of sources of some specific topic. The purpose of the critical literature review is to have an overview of some area of research that has been done on a particular subject and also to verify the sources obtained for the purpose of reviewing.