Due to their exclusive features, dendrimers have focused a great attention over the past few years. Since they have unique characteristics such as hyper branching, well-defined spherical structure, high compatibility with the biological systems, uniform size, water solubility, modifiable surface functionality and available internal cavities these are the reason why they are of eminent interest in drug-delivery applications. In addition to the high level of control over the dendritic structure it is referred as ideal carriers. The unique structure of dendrimers having the greatest impact on their physical and chemical properties. They grow outside from the core-shell which again reacts with monomers and having one reactive or two dormant molecules. Dendrimers are responsible for their wide range of applications including medical, biomedical areas and other innovative areas. The bioactive agents or APIs may be encapsulated into the interior void spaces of the dendrimers or it can be conjugated with the dendrimer surface. Hence, it helps to overcoming the challenges for few drugs which having lower water solubility, cell membrane permeability. In this chapter, we are going to discuss a brief introduction, synthesis, classification and other essential elements of dendrimers.