Wireless keyboards and mice – problems and pitfalls found therein. Number one thing the users forget is when you have a wireless device you need batteries for it. So I would suggest having some spares in the drawer just in case you need them. The keyboard uses three AA batteries and the mouse uses two of the same type. As always, buy good brands because a corroded battery can destroy your wireless device. Always keep in mind your wireless device can walk away and be hard to locate if your six year old decides it makes a great toy. I always keep a wired mouse and keyboard handy for troubleshooting problems on my Macintosh computer. Those directions that say "start up with the C key held down" don't work with a wireless device so be prepared. If you have an old computer that uses a wired USB keyboard and mouse just hang on to them; they will work fine with your new computer as an emergency backup for those times you need one. Something else to keep in mind is that the Magic Mouse has an on/off switch so be sure and turn it off if you are not going to use it the rest of the day. This will make your batteries last longer. When you are turning the mouse back on to use it, movement of the cursor is not instant. On my Mac Mini, it takes about 30 seconds moving the mouse to wake it up.