Triggering is used to make a stable display of an oscilloscope measurement. This video demonstrates how to setup and adjust the trigger settings in the Multi Channel oscilloscope software to make a stable displayed measurement.
The video shows how to use pre samples to view part of the signal before the trigger moment, and explains how you can change the trigger level and hysteresis. By using proper settings, a signal can be displayed without jittering.
See also more information about triggering.