What Is MobileSync & Why Is It Taking Up So Much Memory - Mac OS X

After running Disk Inspector I have discovered that a folder named "MobileSync" is taking up 40GB of data. This is the folder where iTunes stores backups of your mobile devices, such as iPad and iPhone. iTunes has a bad habit of keeping multiple copies and you need to clean out the old backups. This can be done in iTunes under iTunes >> Preferences >> Devices. Then Delete the old backups.