A doorknob is a rounded handle used to open and close doors. Typically made of materials like metal, plastic, or glass, doorknobs are designed to be grasped and turned. They are often attached to a door with a spindle that connects to a latch mechanism, allowing the door to lock or unlock. Doorknobs come in various styles and finishes, making them both functional and decorative. Some common types include privacy doorknobs, which are used in bathrooms, and entry doorknobs, which are designed for exterior doors. Proper installation and maintenance can ensure their longevity and smooth operation.