identifying color of the volume bars

What does the volume bar color means ?

If the volume is high that means the delivered and traded quantity is higher. But what does the color of the bars signify ?

AFAIK, the color of the volume bar matches the color of the price candle for the same time-period.
i.e. it highlights whether

  • the closing-price was higher than opening-price (green)
    or
  • the closing-price was lower than opening-price (red)

The information conveyed by the color of the volume-bar is redudndant in the above screenshot.
However, if one is not using colored price-candles in the chart,
then the color of the volume-bar can be the source of the information
on the price movement between open and close.

Colour is insignificant in case of volume ,so to make it simple for understanding the volume you can make all the bar in one colour