The periodic changes UPSC has undergone in its examination format include shifting from a two-stage preliminary and main exam to integrating an interview round. The introduction of negative marking in prelims emphasizes the need for strategic answering. Modifications in the syllabus reflect evolving socio-political dynamics and emphasize current affairs comprehension. Additionally, adapting questions to evaluate analytical and problem-solving skills rather than rote memorization demonstrates the commission’s intent to innovate. Tracking these changes helps candidates tailor their preparation to meet the exam's evolving demands effectively.