Nanogels combine the characteristics of nanomaterials with hydrogels. To meet the expanding demands from various areas, a sizable number of nanogels have been designed and manufactured using the emulsion solvent diffusion nano precipitated method, emulsion evaporation of the solvent method, reverse micellar method and modified diffusion emulsification method. Thermosensitive nanogel, pH-sensitive nanogel, ultrasound-sensitive magnetic response, response to multiple stimuli, chain transfer polymerization, photo-induced crosslinking polymerization and modifications for active targeting are the types of nanogels based on response towards stimuli and polysaccharide, chitosan, pullulan, hyaluronic acid, alginate, cyclodextrin, gum acacia, protein are used to prepare nanogel. Nanogels have considerable potential and novelty within the biomedical sector due to their uniformity, adjustable dimensions, little toxicity, resilience in the presence of serum, and capacity for responsive behavior with a comparatively high drug encapsulation capacity. Nanogels have considerable potential in bioactive substance delivery, organ targeting, and chemotherapy. The article highlighted the preparation, types, evaluation and applicability of nanogel as a targeted delivery system.