The National Defence Academy (NDA) is a joint services academy for the Indian Armed Forces located in Pune, where cadets from the Army, Navy, and Air Force train together. Admissions involve a written exam followed by an SSB interview, with eligibility criteria including nationality, age limits, and educational qualifications. The NDA exam consists of two papers: Mathematics and a General Ability Test, and preparation tips emphasize early study, understanding concepts, and practicing past papers.