A picture is worth a thousand words. This is 100% true about employee time tracking. It's one thing to know how much time they worked, and another thing what exactly they did. One of the best ways to get this information is by looking at screenshots. TimeVizor will capture screenshots at required intervals and display them in a convenient way.
It's only up to you to set the intervals for screenshots capture: once in 10, 15, 20, 30, 45 or 60 minutes. With a newly-hired employee, it makes sense to set up the most frequent monitoring, while long-time and trusted employees can be controlled sparingly. You can also disable screen capture altogether.
A screenshot is not a mere image. Each screenshot is accompanied by the statistics of keyboard and mouse activity and blacklisted apps and sites employees opened during this time period. You can also browse the full list of opened apps.
Screen capturing allows for verification of employees' work even with a high mouse and/or keyboard activity. Suppose an employee starts imitating key presses or mouse movements by some technical twists. In this case, only screenshots will let you determine the absence of real work.