Hisnul Muslim also known as Fortress of the Muslim or Invocations from the Qur'an and Sunnah, is a popular compilation of supplications (dua) and prayers derived from the teachings of Islam. It is a pocket-sized book that serves as a comprehensive collection of various prayers and supplications for Muslims to recite in their daily lives.

The book is primarily based on the Qur'an and the Hadith (sayings and actions of Prophet Muhammad, peace be upon him). It is organized thematically, with sections covering different aspects of a Muslim's life, such as morning and evening supplications, prayers for specific occasions, protection from evil, seeking forgiveness, and seeking guidance.

Hisnul Muslim is designed to be easily accessible and user-friendly. It provides the original Arabic text of each supplication along with its transliteration and translation in various languages. This makes it suitable for Muslims of different linguistic backgrounds to understand and recite the prayers effectively.

The compilation includes supplications for various situations, such as before and after prayer, before sleeping, upon waking up, before and after eating, before traveling, and during times of difficulty or distress. It also contains prayers for seeking Allah's protection, expressing gratitude, and seeking blessings for oneself and others.

The book is widely used by Muslims around the world as a practical guide for incorporating supplications into their daily routines. It serves as a constant reminder to remember Allah and seek His guidance and blessings in all aspects of life.

Overall, Hisnul Muslim is a valuable resource for Muslims who wish to deepen their connection with Allah and enhance their spiritual practice through the recitation of supplications and prayers in accordance with the teachings of Islam.