The value area is bounded by the value area high (VAH) and value area low (VAL). Inside it, price is considered accepted; outside it, price is either finding new value or about to snap back.
Traders use yesterday's value area as today's reference: opening inside it suggests a range day, opening outside it suggests a trend day if price is accepted there.
Example: yesterday's value area on ES was 5,010 to 5,030 with a point-of-control at 5,022. Today opens at 5,038 and holds above 5,030 for the first hour, which is acceptance above value.
Related: volume-profile, point-of-control, range, trend