Volume is representative of how many shares change hands in a stock, and as such, it indicates the interest in a security. Since each stock is different, and has a different amount of shares outstanding, volume can be compared to historical volume within a stock to spot changes, or compared to other stocks to find which are suitable for trading. Volume is also used to confirm price trends, breakouts, and spot potential reversals. Volume has also been implemented into indicators, which can aid in analyzing stocks (and other markets).
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