In the medical field, the active ingredient is in the form of solid particles for 90% of all medicines. Because of development in nanotechnology, it is now possible to produce drug nanoparticles that can be utilised in a variety of innovative ways according to the need. From few decades, there had been considerable interest in area of nanotechnology and many works have been done in order to deliver drugs using particulate delivery systems (nanoparticles) as carriers for small and large molecules. Development of nanoparticles arose in response to vast and broad medical needs, common to a number of therapeutic areas and targets. The potential advantages of nanoparticles as oral drug carriers are enhancement of bioavailability, delivery of vaccine antigens to the gut-associated lymphoid tissues (GALT), controlled release, and reduction of the gastrointestinal irritation caused by drugs. Beside this nanoparticles also offer other route of administrations. Various polymers have been used in the formulation of nanoparticles for drug delivery research to increase therapeutic benefit, while minimising side effects. This review article laid emphasis on various aspects of nanoparticles, their uptake, formulation, characterisation and applications of nanoparticles approach in delivery of drugs molecules and genes.