Genetics is a branch of biology that deals with heredity and the passing on of characteristics of all living organisms from one generation to the next. Genetics can be divided into three major areas of study.

1. molecular genetics

2. transmission genetics

3. population genetics

        Molecular genetics deals with the structure of all genes. Genes are the threadlike structures called chromosomes, which are located in cells. The are made up of DNA (deoxyribonucleic acid.) DNA carries genetic codes that make up the characteristics of all living organisms. Molecular genetics study processes as replication and mutation. Replication if the process by which cells duplicate DNA molecules. Mutation is a permanent change in the gene. Gene mutations can alter an organism's traits. Advances in molecular genetics have led to the development of genetic engineering.

       Transmission genetics is the approach to the study of heredity. It deals with patterns of inheritance by using and extending the laws that were discovered by Gregor Mendel. Transmission genetics study how genes are transmitted. This is done by experimenting and tracking variations in the patterns of inheritance of a trait over generations. New discoveries in transmission genetics can have many uses in our live. For example, the discovery of a gene that passes down a disorder or a disease can help identify which individuals are at a risk of developing that condition through heredity.

       Population genetics focuses on processes that change the relative frequency of genes in a population through time. This often studies how processes of evolution (natural selection, mutation) interact with one another. Population geneticists believe that an understanding of the processes of evolution can help explain the diversity of life on Earth.