What exactly is a magnetic braking system on a baitcasting reel?  What purpose does it serve and how would one go about adjusting it?

I remember seeing something about it on a fishing show and had no clue what they where talking about.  At first I thought they were talking about the tension knob you adjust for the weight of the lure your casting, but after watching the show more, it sounds like they are talking about something different.

Reels with such a system have magnets mounted inside the sideplate opposite the handle.  There should be a dial on that side that moves the magnets closer to, or further from the side of the spool.  The closer they are, the more they slow the spool down.

A magnetic brake system is the one that controls the spool speed rotation based on the principle of magnetic attraction between a magnet and the material of the spool ( or a rotor ) itself.

Closer proximity of the magnet ( or magnets ) to the spool ( or it 's rotor ) the more magnetic attraction thus the more braking power it exerts.

How do you adjust it ? with a dial.

All Daiwa bc reels have a magnetic braking system.