There are a few simple yet distinct differences between automatic and quartz watches.

1.  Quartz watches are battery operated while automatic watches are self winding.

2.  You can lay down a quatz watch for a day a week or even a month and when you pick it up it will have the exact time.  Where an automatic watch will stop working roughly 2 days after it is taken off.  Automatic watches must be worn for 12 active hours a day for them to keep on running.

3.  A quartz watch will keep the precise time until the battery runs out where an automatic watch may gain or lose up to 10 minutes a month and still be considered to be working within it's normal range.

4.  An automatic watch will need to have maintenance (overhaul) performed every 2-3 years, where a quartz watch will need it's battery changed every 1-2 years.

If you plan on alternating between two or more watches, it is recommended to you either purchase quartz watches or buy a watch winder.