A service manual is a comprehensive guide that provides detailed instructions on how to maintain, repair, and troubleshoot a specific product or system. These manuals are commonly used for various items, including vehicles, appliances, and electronic devices. They typically include diagrams, parts lists, and step-by-step procedures to help users understand the inner workings of the product. Service manuals are essential for technicians and DIY enthusiasts, as they offer valuable information on safety precautions and proper techniques. By following the guidelines in a service manual, users can ensure that they perform repairs correctly and efficiently, ultimately extending the lifespan of the product, such as a car or computer.