Double top:
The double top is a bearish reversal pattern where the price reaches a high two times and it’s unable to break higher on the second attempt. At the same time, the pullback between the two tops should be moderate. The pattern is confirmed once the price breaches the low of the pullback between the two tops.
Double bottom:
The double bottom is a bullish reversal pattern where the price holds a low two times and eventually continues with a higher high. Similarly to the double top, the bounce between the two lows should be moderate. The pattern is confirmed once the price reaches a higher high than the top of the bounce between the two lows.