Essential resources for UPSC exam preparation include standard textbooks, online courses, and current affairs magazines. Key books such as NCERT textsprovide foundational knowledge, while reference materials like Indian Polity by M. Laxmikanth and Indian Economy by Ramesh Singh offer depth in specific subjects. Online platforms can provide interactive materials and frequently updated content. Newspapers like The Hindu or Indian Express are crucial for current affairs, and coaching institutes can offer structured guidance. Combining these resources with a disciplined study plan significantly enhances preparation efficacy.