This review paper aims to provide an overview of the synthesis and applications of nano-dimensional materials. For the last few decades, nanotechnology has emerged as an excellent tool for a wide range of applications due to the phenomenal and splendid properties of materials at the nano-level. It finds applications almost in every sector from industrial applications to biomedical applications. Any particles in the range of 1–100 nm have been considered as NPs. NPs can be synthesized by either of the two ways “bottom-up” and “top-down” approaches. Due to the certain drawbacks of some of the methods which consume chemicals and generate toxic byproducts, green synthesis has been considered the most effective method using various plant extracts. Biogenic synthesis of the NPs by reducing the metal precursors to NPs is safe cost-effective and eco-friendly and it doesn’t utilize any chemicals. Green synthesis, a bottom-up approach is quite efficient for the synthesis of a number of NPs. A comparative study of the synthesis of NPs using various plant extracts has been discussed along with their application.