Technical Analysis : Chart Pattern

1. Double top (reversal formation)
For obvious reasons this is often called an "M-top". The market is failing twice at a resistance and is reversing then sharply. A break of the support would indicate further losses towards the target that can be evaluated through the following procedure. The vertical width of the "M" (price difference) is projected downwards from the breakpoint of the support.

2. Double bottom (reversal formation)
The opposite of Double top. (often called an “W-top”). When the market is failing twice at a support and is reversing then sharply. A break of the resistance would indicate further rising towards the target that can be evaluated through the following procedure. The vertical width of the “W” (price difference) is projected downwards from the breakpoint of the resistance.

3. Triangle
The triangle formation can be quite difficult to analyse and the fact that a few different types of triangles exist doesn't make this task any easier. Furthermore a triangle is most commonly just a pause in a trend (continuation pattern) but can also terminate a trend (reversal formation).

4. Head and Shoulders
Formation of left shoulder forms a new high with a corrective dip, next rally forms higher high = head, correction from head goes below high of left shoulder and near as low of the left shoulder correction, breaching up trend line, rally of right shoulder does not breach head high, retracing half to three quarters of head correction..