A local backup is a backup that resides on a storage device close to you.  Local backups include:

• CD/DVD/Blu-ray
• External hard drives
• Network attached storage (NAS) devices
• Flash drives
• USB thumb drives
• Tape

Advantages

You are in control of the device used to store your backup.  It offers faster backup and restore speeds than cloud-based services, since the speed is not limited by the internet connection.  Backups to a USB 3.0 hard drive are typically around 100 megabytes per second – or 800 megabits per second.  That’s up to 80x faster than the typical residential internet speed.

Disadvantages

There’s a higher chance of data loss when backups are stored in the same location as the data being backed up.  It offers no protection from fire, theft, and other disasters that could destroy both your backups and your files.