Developed comprehensive documentation for Kafka consumer group rebalancing within the kyungjunleeme/kafka_study repository, focusing on distributed systems concepts and best practices. The work detailed both eager and cooperative rebalancing strategies, clarified the roles of Group Coordinator and Consumer Leader, and explained static group membership and configuration settings relevant to consumer behavior. Using Markdown, the documentation also addressed offset management through automatic and manual commits, as well as the behavior of rebalance listeners during partition assignment and revocation. This targeted knowledge base enhancement aimed to streamline onboarding, reduce misconfigurations, and support faster troubleshooting for teams working with Kafka consumer groups.