One of the biggest disadvantages of a USB stick is the fact that you can only use it for one operating system. So if you use your USB flash drive stick on your Mac it will only be usable for Mac OS X, when connecting it to your Windows system you won’t be able to read any data.
By formatting your USB stick in a certain way, you can use it for both operating systems. To format the USB stick you do not have to use any 3rd party application, the standard Mac OS X Disk Utility does this job perfectly.
Lets start ‘Disk Utility’ (Applications > Utilities > Disk Utility). On the left column select the USB stick that you want to format. Select the tab ‘Erase’ and if format MS-DOS (FAT), you can change the name if you like. When you have setup everything right, hit the ‘Erase’ button and make sure that you transferred the files from your USB stick before you confirm and start formatting.
After completing these steps you can use your USB stick for both Mac OS X and Windows. The use of the FAT file system however does have some disadvantages; the biggest drawback is that you can’t use files larger than 4GB.