This guide is specifically prepared for investors trading cryptocurrencies like Bitcoin, Ethereum, and others. The core focus is teaching how to use "trading volume" to judge market trends and assist trading. Here's a simple summary:

1. Understand the basics: What exactly is trading volume?

Trading volume refers to the total amount of cryptocurrency traded within a certain period. Its main role is to assess market activity and capital participation. The key is to look at the "price-volume relationship": when prices rise, trading volume should increase simultaneously, indicating that the rally is supported by funds and the trend is reliable; if prices go up but volume shrinks (not many traders involved), the upward movement is likely unsustainable and may reverse.

A little extra knowledge: different exchanges may have varying rules for calculating volume, which can sometimes be manipulated; on-chain data (actual transfer records on the blockchain) can exclude fake trades and provide more reliable reference.

2. How to interpret trading volume across different timeframes?

- Intraday short-term (same day): focus on 1-minute and 5-minute volume. For example, if the price breaks above the previous day's high with low volume, it might be a "false breakout"; if the price hits a new high but volume doesn't follow, a pullback is likely.

- Mid-term (weeks to months): monitor 5-day and 20-day average volume. If short-term average volume remains higher than long-term, it indicates a stable uptrend; a breakout from a sideways range with increased volume on weekly charts may signal the start of a mid-term rally.

- Long-term (major trend): combine with large on-chain fund movements. For instance, in the bottom phase, if volume keeps increasing but prices stay stable, it could be "smart money" quietly accumulating, hinting at a big move ahead.

3. How to use volume in extreme market conditions (sharp rise/fall, sideways)?

- During sharp rises: if prices keep climbing but volume gradually decreases, it signals a potential top; a breakout with historically large volume suggests a solid move with room to run; if volume suddenly spikes but price stalls, it might be a trap set by big players to lure retail investors.

- During sharp declines: consider the "pyramid averaging" method (adding small amounts as the price drops), but stop adding after a 10% drop to avoid further losses; prioritize reducing positions to control risk; also, monitor large on-chain fund movements to avoid bottom-fishing at the wrong time.

- During sideways consolidation: volume drops below 30% of the yearly average, indicating market sentiment is low and bulls and bears are at a stalemate; a subsequent increase in volume usually precedes a breakout—either upward or downward.

4. Differences in volume analysis between mainstream coins and altcoins

- Mainstream coins (Bitcoin, Ethereum): more reliable, with clear volume-price patterns (volume increases on uptrends, decreases on downtrends), ample liquidity, and large trades generally won't significantly impact prices; can also incorporate derivatives volume (futures, options) to confirm trends.

- Altcoins: higher risk, small funds can cause sharp price swings; sudden volume surges often indicate hype or manipulation by whales; the trend may lack sustainability, and you might see "price rising but volume falling" anomalies; always cross-check large on-chain transfers to verify signals.

5. How to apply these techniques in actual trading?

- Master basic indicators: such as OBV (to judge capital flow) and VWAP (institutional average cost), avoiding relying solely on price signals, which can lead to misjudgments.

- Multi-dimensional validation: for key breakouts, volume should be at least 1.5 times the daily average; combine data from different timeframes and exchanges to avoid false signals from a single platform.

- Practice + strict risk control: test strategies with demo accounts first (e.g., "buy on volume breakout, sell on volume decline"), and in real trading, set strict stop-loss and take-profit levels; never base decisions solely on volume signals.

- Adjust strategies flexibly: different market phases require different volume interpretations; altcoins are suitable for short-term trading with quick entries and exits, while mainstream coins can be part of long-term plans—don't stick to one method for all scenarios.

Summary: Trading volume is a core tool for judging market authenticity and understanding capital movements. The key is to adapt its use based on different timeframes, coins, and market conditions, combined with other data and risk management rules, to effectively improve trading success rates.