The term ‘Biotechnology’ was coined in the year 1919 by an agricultural engineer Karoly Ereky; hence he is called the father of Biotechnology. The techniques of using live organisms or enzymes from organisms to produce products and processes useful to humans. It discusses the two essential Principles of Biotechnology – Genetic engineering and Bioprocess engineering. It briefly discusses the tools of recombinant DNA technology such as restriction enzymes, ligases, polymerase enzymes, vectors and host entities. Processes of recombinant DNA technology are the isolation of DNA, fragmentation of DNA by restriction endonucleases, isolation of the desired DNA fragment, ligation of the DNA fragment into a vector, transferring the recombinant DNA into the host, culturing the host cells in a medium at large scale and extraction of the desired product.