Authentic Hadith refers to the sayings, actions, and approvals of the Prophet Muhammad that have been verified for their reliability and accuracy. These narrations are crucial for understanding Islamic teachings and practices, as they provide context and guidance beyond the Quran. To be classified as authentic, a Hadith must have a strong chain of transmission, known as isnad, and must be free from any defects or inconsistencies. Scholars of Hadith study these narrations meticulously to ensure they meet the criteria for authenticity, which helps preserve the teachings of Islam.