Drug delivery is the technique for delivering the pharmaceutically active compound to accomplish a therapeutic impact on humans or animals. Most normal strategies for medication delivery system incorporate the oral (through the mouth), topical (skin), inhalation route, transparent route (injection into the systemic flow), and submucosal (nasal, buccal, sublingual, vaginal, ocular, and rectal). The traditional release dosage form of drug delivery involves the dosing, intended to offer an immediate release (IR) of the drug contained in the delivery system following its systemic administration. In the new era, the topical route has also been employed to deliver the drugs to systemic circulation with minimal side effects and toxicity. It is probable that the oral route manages not less than 90% of all medications used to deliver systemically. The drug-dose maintenance in the body is accomplished by repeated administration of the dosage form. Over the past 20 years, new methodologies have been developed to control and improve treatment-related parameters such as the rate of administration, the period of treatment, and the target delivery index.