BOS - break of strucuture. I will use market structure bullish or bearish to understand if the institutions are buying or selling a financial asset.
To spot a bullish / bearish market structure we should see a higher highs and higher lows and viceversa, to spot the continuation of the bullish market structure we should see bullish price action above the last old high in the structure this is the BOS.
BOS for me is a confirmation that price will go higher after the retracement and we are still in a bullish move
WHAT IS CHOCH?
CHOCH - change of character. Also known as reversal, when the price fails to make a new higher high or lower low, then the price broke the structure and continue in other direction.