Offline Time Tracking works in two ways:
Time Tracking software application starts working in the background as soon as your employee logs into his/her account. It tracks when the employee was on his/her desk and when the employee kept the desktop idle. Phone calls, meetings, etc., can be the reason why the employee was not using the desktop. This is called Offline Tracking.
The internet connection gets disrupted; however, the employee continues working on office applications that don't require connectivity. In this case, when the internet connection gets restored, the offline work gets synchronized and uploaded to the time tracking software. This is also referred to as offline time tracking. A few time trackers have this feature.