Trading volume is an important tool for assessing the validity of key levels. Whether it's support or resistance, trading volume directly influences the "magnitude" of price movements.

In simple terms:
- **When trading volume is high, breaking through or holding a key level is more reliable.** For example, if Bitcoin's price hits a strong support level with massive buy orders, it generally indicates that a lot of funds are entering the market, increasing the likelihood that the support will hold.
- **When trading volume is low, key levels are more likely to be "false breakouts."** If a resistance level is broken with only small trading volume, it's often a fake breakout, and the market may quickly reverse.

Here's a simple analogy: a key level is like a door, and trading volume is how many people are pushing it. When many people push, the door opens (breaks resistance); when few people push, the door doesn't budge (breakout fails).

Common operational suggestions:
- When breaking through a key level, if accompanied by a significant increase in volume, consider following the trend.
- If the breakout occurs with declining volume, be cautious and avoid rushing in, as it might be a false breakout.

Risk reminder: The relationship between price and volume is just an auxiliary indicator. You shouldn't rely solely on trading volume to make decisions; it's important to consider the overall trend and news environment. The crypto market moves quickly, so remember to set stop-losses and avoid being too aggressive.

By the way, are you more interested in technical analysis or investment logic based on fundamentals? I can go into more detail about how trading volume is practically used in different strategies.