What is the most common fixed lock in use today?

The cylindrical lock is the most common fixed lock in use today because of its widespread application in residential and commercial buildings. Its design features a cylindrical body that houses the locking mechanism, making it relatively easy to install and operate. The simplicity and functionality of the cylindrical lock contribute to its popularity; it often provides a good balance of security, cost-effectiveness, and ease of use.

Moreover, these locks typically have various finishes and styles, which can complement a range of architectural designs, making them a versatile choice. Unlike some other types of locks, such as mortise locks or deadbolts, cylindrical locks are easier to manufacture and install, which has contributed to their common usage throughout everyday environments.

While other types of locks also serve important functions, the combination of accessibility, affordability, and convenience offered by the cylindrical lock solidifies its status as the most prevalent choice in current lock systems.