Trigger lines define the trend in a different way. The colors are user selectable and the chart shows two sets of lines. The blue/red lines are called the big triggers while the cyan/magenta lines are called the small triggers.
The big trigger lines shows the lines crossing and turning blue which indicates the main trend is up and when they cross and turn red the main trend is down. The big trigger lines are longer term and show a bigger trend than the small trigger lines.
The small triggers show the immediate trend of the market and turn much faster with price than the large triggers.