What Time Machine DoesWith Time Machine, you can back up your MacBook to many different destinations. These include and external hard drive, a USB flash drive, a FireWire drive, or an AirPort Time Capsule on a networked computer. Your MacBook may have either USB, FireWire, or ThunderBolt ports you can connect external hard drives, and flash drives to for backup purposes.
Depending on how you set up Time Machine, it can keep hourly backups, daily backups for up to a month, and weekly backups. Keep in mind the oldest backups will be eliminated if your backup drive gets full.