Glossary
Change of character CHoCH
In short
A change of character (CHoCH) is the first break of structure against the current trend, for example the first close above a lower high in a downtrend. It is an early sign that the trend may turn.

An early signal, not a confirmed turn
A CHoCH says that the old trend has lost its rhythm. It does not yet say that a new trend has started. Many traders wait until the new direction confirms itself with a break of structure.
Internal and swing structure
On the small internal swings, changes of character happen often. A CHoCH on the larger swing structure is rarer and carries more weight. AE Market Structure tracks both and shows them separately.