From Sudopedia, the free Sudoku reference guide

From Sudopedia

The broken wing pattern in example 1 has 4 strong links and a single weak link between the cells in row 5. The pattern is a classic example of a simple color wrap. If you start coloring either of the cells in row 5 red the other one will also be red, and therfore the blue cells will be X. Note that this is the simplest pattern for a color wrap. As such I call it a color wrap wing and it is one of the patterns that I look for in a puzzle. Note that the simplest type of XY-chain is called an XY-wing and is listed as a pattern technique. The 5 cell pattern is as easy to spot as a Sashimi X-wing which also has 5 cells. Nienhaus 7-20-08

The broken wing pattern in example 2 is also worth remembering. It has 3 strong links which are broken up by 2 weak links into a single link color chain in column 2 and a two link color chain in columns 5 and 6. Since the ends of the two link chain must be the same color and each is a peer of a cell in the one link chain, they cannot be X and therefore r1c5 is X. After removing x as a candidate from r2c4 and r5c6, the one link chain and the guardian cells form an x-wing, so you still get the same eliminations as in the guardain technique to add to the 2 eliminations obtained from the multi-coloring technique. Nienhaus 7-22-08