You might be confused by two instances where VWAP appears in the material.
First, VWAP is Volume Weighted Avg Price, it’s used to measure how good a price the trader is getting in the market relative to what everyone else is trading at. VWAP is the execution price everyone got, on average. If the trader did better (higher on a sell or lower on a buy) then he did good.
Second, Simple Logical Participation trading algorithms sometimes are set up to trade in order to beat VWAP. Earlier, I said “aims to minimize VWAP”, but actually I meant, “aims to beat VWAP”.
Don’t ask me how a VWAP algorithm would work, that’s probably a question for compscikid.