In computing, a login session is the period of activity between a user logging in and logging out of a (multi-user) system.
On Unix and Unix-like operating systems, a login session takes one of two main forms:
On Windows NT-based systems, login sessions are maintained by the kernel and control of them is within the purview of the Local Security Authority Subsystem Service (LSA). winlogon
responds to the secure attention key, requests the LSA to create login sessions on login, and terminates all of the processes belonging to a login session on logout.