When we think about how to measure volume in the market one of the keys is Order flow . It plays a role by telling us what the other traders have done in the market and are currently doing and this provides valuable clues and potential opportunities to trade.
An Order Flow trader can actually see exactly what is happening in the market as it happens. Once you are able to understand what is happening in the present, you are able to make far better decisions about what might happen in the future. Order Flow provides traders with vision into market activity.