Introduction:
Political Science and International Relations (PSIR) is an important subject for UPSC aspirants. To excel in this subject, it is crucial to have access to study materials and resources that provide comprehensive and reliable content. Fortunately, there are several online platforms and websites that offer study material and resources for PSIR.

EduRev:
One such platform is EduRev, which is a popular online learning website that provides study materials, notes, and resources for various subjects, including PSIR. EduRev offers a wide range of study materials, including textbooks, lecture notes, practice questions, and previous years' question papers. The platform also has a community of educators and learners who actively engage in discussions and share valuable insights regarding PSIR.

StudyIQ:
StudyIQ is another online platform that provides study materials and resources for UPSC preparation, including PSIR. They offer comprehensive video lectures on various topics related to PSIR, which are beneficial for visual learners. These video lectures cover important theories, concepts, and thinkers in the field of political science and international relations. StudyIQ also provides downloadable notes and study materials that can be accessed offline.

BYJU's:
BYJU's, a renowned online learning platform, offers comprehensive study materials and resources for PSIR. They provide video lectures that cover various topics in PSIR in a detailed and engaging manner. Additionally, BYJU's offers downloadable PDFs and e-books that contain in-depth explanations and analysis of key concepts, theories, and thinkers in the field of political science and international relations.

InsightIAS:
InsightIAS is a popular website that offers study materials and resources specifically designed for UPSC aspirants. They provide comprehensive notes, articles, and current affairs analysis related to PSIR. InsightIAS also conducts regular webinars and interactive sessions with subject matter experts to clarify doubts and provide additional guidance to students.

Civilsdaily:
Civilsdaily is an online platform that offers daily current affairs analysis and study materials for UPSC preparation. They provide a dedicated section for PSIR, where they cover important current affairs topics, theories, and concepts in a concise and easy-to-understand manner. Civilsdaily also offers a mobile app that allows users to access study materials and resources on the go.

In conclusion, several online platforms and websites offer study materials and resources for PSIR. EduRev, StudyIQ, BYJU's, InsightIAS, and Civilsdaily are some of the prominent platforms that provide comprehensive and reliable study materials, notes, videos, and current affairs analysis for UPSC aspirants. These resources can greatly aid in the preparation for the PSIR subject and help students excel in their exams.