CDS stands for Combined Defence Services. It is an exam conducted by the Union Public Service Commission (UPSC) twice a year(April and September) to recruit candidates for IMA (Indian Military Academy), INA(Indian Naval Academy), AFA (Air Force Academy), and OTA (Officers' Training Academy).While some people also refer CDS full form as Chief of Defence Staff, this rank is given to the head of the Indian Armed Forces
The selection process comprises written exam and SSB interview. The minimum educational qualification needed to appear for CDS exam is graduation from a recognised Indian university