Harmonics Glossary

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Bat, Crab, Deep Crab, Gartley, Butterfly, Shark, Alt Bat, ABCD, Shark (Can be both) - Harmonic Patterns

Bat, Gartley - Retracement (Ret) patterns
Crab, Deep Crab, Alt Bat, Butterfly, Shark (can be both) - Extension (Ext) patterns

Fib measurement - A fibonacci tool is used to measure between to price points on a chart. The levels between (Ret) and beyond (Ext) those points are then displayed.

XA - The fib measurement from X to A
BC - The Fib measurement from BC to which can give a retracement (Ret) or extension (Ext)
Ext - A move that extends beyond the XA measurement. If XA is 100, the extension is greater than a 100.
Ret - A retracement move is a move back towards where it came from. So, always contained within the XA and greater than 0 & less than 100.
Terminal Bar (Tbar) - Pattern Completion at the XA

HSI - Harmonic Strength Indicator.
HOP - Harmonic Optimal Price

Target 1 (T1) - The first price target of the pattern in question
Target 2 (T2) - The second price target of the pattern in question

The harmonic framework has specific and measurable moves. These are described below...

Type 1 - The anticipated move after pattern completion towards Target 1. Needs further confirmation signals within the price action at Tbar+
Type 2 Return - Once the Type 1 is completed we anticipate a Return move back to and a retest of XA. Again, specific signals/confirmation is required
Type 3 Reversal - With a Type 1 and Type 2 Return complete, we can anticpate the reversal move towards Target 2. with a Type 2 Reversal move. Again, there is a mandatory a required specific signalling event.

Some Other Technical Analysis Resources (Courtesy of JC)
https://www.investorsintelligence.com/x/glossary.html
https://www.ig.com/uk/glossary-trading-terms#R