The National Defence Academy (NDA) is the Joint Services academy of the Indian Armed Forces, where cadets of the three services, the Army, the Navy and the Air Force train together before they go on to respective service academies for further pre-commissioning training.
The "Combined Defence Services" (CDS) Examination is conducted twice a year by the Union Public Service Commission for recruitment into the Indian Military Academy, Officers Training Academy, Indian Naval Academy and Indian Air Force Academy.
AFCAT is a national level competitive exam conducted by the Indian Air Force (IAF) to select officers for all its branches, except for the medical and dental branches. For all entries other than NDA and CDSE and for all branches, candidates have to undergo the AFCAT. The test is conducted twice a year in February and August
The Merchant Navy is a non-combatant commercial fleet, which deals with transporting cargo and occasionally passengers, by sea. Their ships may belong to various private and government shipping companies. In Fact the Merchant Navy, is the backbone of International trade, carrying cargo across the globe.
Air Forece X group indicates fully Technical and Y group consists of mostly Non-Tech tradesmen and some Technical trades too. Air Warriors are selected under these groups and Group X tradesmen draw slightly higher range of salary than Group Y. The eligibility also varies according to different trades or branch.