Online study materials play a pivotal role in UPSC preparation by providing accessible, diverse, and comprehensive resources. They offer current syllabus-aligned content, including curated notes, video lectures, and practice tests, aiding self-paced learning. Platforms like online forums and social media allow aspirants to engage with peers, share resources, and clarify doubts. Additionally, access to online mock tests helps candidates familiarize themselves with exam patterns and improve time management. However, candidates should critically evaluate the quality of online materials to ensure effective learning and essential concept mastery for successful examination preparation.