It has a number of functions, including seeking out the enemy and securing ground in advance of the main force.
The vanguard derives from the traditional division of a medieval army into three battles or wards; the Van, the Main (or Middle), and the Rear.
This consisted of: In an English force of the period, the foreriders of the vanguard would be accompanied by the harbingers, whose job was to locate lodgings for the army for the following night.
[3] In modern times, the word can also be referred to as a group of people leading the way in new developments or ideas.
Forward detachments brought together the mobile (motorized or mechanized) elements of the parent formation to play an exploitation role once a breakthrough of the German lines occurred.