Genetics is the study of single gene and genomics is the study of the all genes in the genome. Genomics includes Functional genomics, Structural genomics, Comparative genomics, Epigenomics, Pharmacogenomics. Genomics examines the function and structure of genomes and also examines the all genes and their inter relationships in growth and development of the organism. Review articles are the summary of current state of understanding on a particular research topic. They analyze or discuss research previously published by scientist and academicians rather than reporting novel research results. Review article comes in the form of systematic reviews and literature reviews and are a form of secondary literature. Systematic reviews determine an objective list of criteria, and find all previously published original research papers that meet the criteria. They then compare the results presented in these papers.