An exponential moving average weights recent prices more heavily than older ones. The 20, 50 and 200 periods describe the short, medium and long-term direction on the chart you are looking at.
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When the 20 is above the 50 and the 50 is above the 200, and all three slope upward, the chart is in an orderly uptrend. When they are tangled and flat, the market is ranging and trend tools lose their value.
Crossovers lag by design. Use the averages to decide which direction you favour, then use structure and levels to decide where and when to act.
On the one-hour chart, all three EMAs slope up in order. Price pulls back to the EMA 20, which sits near a previous resistance turned support. The trader looks for a lower-timeframe break of structure upward there instead of buying the touch blindly.