What Does System Time Mean?
System time is the current time and date that the computer system keeps track of so that applications running on the system have ready access to accurate time. Most computer systems base their system time on the current time in relation to Greenwich, England, which is called the coordinated universal time (UTC), and each time zone is designated as being ahead or behind by a specific number of hours.
Techopedia Explains System Time
The system time is maintained in relation to the system clock, which is implemented based on the number of ticks that have occurred since an arbitrary starting date called the "epoch," usually the time from which the computer system was first turned on or an agreed-upon specific date such as the Unix Epoch, which starts at the first of January 1970. So during the first startup of the system, the current system time is set to the epoch date and then moves on from there. Depending on the system, the correct time either is automatically synced with UTC time on the Internet or has to be manually set by the user.