A victory point is a node used in capture and hold there are normally three on a map. When a team holds the majority of the nodes there is a score bar on the top both teams have 500 points when you hold the victory points the other team will slowly lose points if held long enough the other team will drop to zero and you'll win.
Tips for holding
If you a defenseive hero like a techpirest or an mekboy build turrets in cover around the victory point and a relay beacon right outside the point so your troops can quickly reinforce.
Place Suppressive units in cover and ranged infantry are best at holding the victory point.
Place some anti-vehicular infantry around the victory point.