The flasher is the little device that makes the lights blink when you indicate a turn. It's a small cylindrical can located underneath the dash or stuck in the fuse block. If you park in a very quiet place and indicate a turn, you should be able to hear it going 'click-click' in time with the lights.

If this little device is undersized for your amount of lights, it will blink rapidly. Pull it out, take it to your auto parts store and ask for a heavy-duty version.

This is assuming that this is your problem. The more lights you have blinking left or right, the more current you are drawing which means the flasher will blink faster.

Stuart