To understand the difference between a cylinder and a lock, one must first understand everything about the machine that can close the door.
The lock time refers to the entire mechanism. Thus, the lock is a set of hardware that allows the door to be closed and opened, which will include, but is not required to be, the cylinder.
A cylinder, on the other hand, is a device that attaches to a lock and has a small piston and a spring that is pressed properly by a key to lock/lock the open/close mechanism. Due to this, the role of the cylinder is transmitted to the force of the key to the lock. There are many models, but now the most popular model in Italy is the European cylinder with round and oval profiles.
From a practical point of view, it can be said that the lock is the largest, and it can open and close the heaviest door. A cylinder, on the other hand, is something you find in the lock that has a weight and size.