Trading Volume is a technical indicator which represents the overall activity of an asset or a market. The volume indicator is used to measure the total amount of a given financial asset that has been traded in a specific period of time.
By looking at volume patterns over time, traders can better understand the strengths of advances and declines in assets as well as in markets in general.
Traders often use trading volume to confirm the actuality or continuation of a trend, or a reversal of a trend.
If trading volume increases, prices generally move in the same direction. Thus if an asset is moving higher in an uptrend, the volume of the asset should also increase and vice versa.