The Fishing reel is a very simple machine in theory, but when you crack it open to explore all of its features it is very complex. There are a lot of moving parts in the fishing reel and it relies on every single one of them. If one of the parts is knocked loose or broken or not lubricated right the fishing reels functionality will not be at its highest.
There are quite a few simple machines in the reel that we dissected. First you have the crank. The crank is the main input device for the whole reel, with the power source being your hand. The crank is on a spindle which drives a gear that drives the drive shaft which drives multiple other parts. Then you have the main gear itself which drives the drive shaft. Also there are screws that hold the fishing reel together. And last but nit least is the drive shaft. It is a simple rod with a few grooves in it.
There are also other various switches and springs which i have not yet found the purpose for. Those parts are the ones that make a little more complex than it should be.
The reel in itself is very lite-weight and very easy to use. Various age groups can use it. They even sell more advanced reels that are made to be lighter and more durable. Also the more advanced reels will have choices on the gear ratio. Being that a 1:20 gear ratio means that one turn of the handle makes the bail or spool turn 20 times, which is also the highest gear ratio you can get for any type of fishing reel. The fishing reel even has a few uses besides fishing. If you really needed to you could use it as a line spool for a kite, or maybe even to play a prank on a friend by reeling a bug across the floor.