Perhaps you have heard crypto traders talk about the stochastics being overbought or oversold and have never quite knew what they were talking about...
Let me clear it up for you.
This is the Stochastic Oscillator:
Any time it reaches extreme levels it would be considered overbought or oversold.
In this one, it would be anything above 80 or below 20.
As you can see it doesn't always work, but it often can give you a clue that prices are about to head the other direction.