Lock function is used to show users when a certain document is in process. However, users with the right permissions on the document can reverse the lock and modify the content of the document.
Any user can receive notifications when a change is made to a specific document or folder. When this service is requested, notifications of any transactions made to the specified file or folder will be displayed in the list of notifications. A manager of a group can make a decision for the whole group on whether they receive notifications or not. Once this service is requested by the manager, all members of the group will receive notifications on the specified file or folder.