What it is
VWAP is the average price paid for a stock, weighted by the volume traded at each price. Session VWAP resets every day. Anchored VWAP starts from a bar you pick and runs forward from there. You might anchor it to an earnings gap, a swing low or the start of a base. It tells you the average cost of everyone who bought since that moment. That is the price where the average buyer goes from winning to losing.
How to use it on the chart
Turn on the AVWAP overlay on any ticker page. It starts from the lowest low in view, and you click a bar to move the anchor. Anchor it to a breakout day and the line shows whether buyers since the breakout are still ahead. A stock riding above a rising anchored VWAP is supported by its own holders. A drop through it means the average buyer since the anchor is now losing money. That is when sellers tend to appear.