When trading is allowed at all, and what has to happen to enter.
A gate is a condition that must be true before anything else is looked at, typically a trend or volatility filter on a slower timeframe.
Entry conditions decide the moment. You can require all of them, any one, or a score such as 2 out of 3.
Gates on a slower timeframe only use candles that have already closed. A 4-hour candle that is still running does not know its close yet; using it would be looking into the future.
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