Complete guide to Compound Interest for competitive exams: basic definition of Compound Interest (interest on principal + accumulated interest), amount formula (A = P(1 + R/100)^T), compound interest formula (CI = A – P), half-yearly compounding (R/2, T×2), quarterly compounding (R/4, T×4), monthly compounding (R/12, T×12), yearly compounding, finding principal when amount and rate given, finding rate when principal and amount given, finding time when principal and amount given, problems on population growth (P(1 + R/100)^T), problems on depreciation (P(1 – R/100)^T), difference between compound interest and simple interest for 2 years (CI – SI = P(R/100)^2), difference for 3 years (CI – SI = P(R/100)^2 × (3 + R/100)), problems on installment (equal annual payments), problems on varying rates for different years, and shortcut tricks for SSC, Banking, Railway, UPSC, and other government exams.