Backup and Reset is an important feature on Android 6.0 Marshmallow. The new feature on Android Marshmallow is very different from other versions of Android, even much different from the backup and reset feature on Android 5.1 Lollipop.
The backup and reset feature on Android Marshmallow allows you to backup all your app data to your Google Account. So that you can restore your device at a later point.
Earlier, Google users had to manually reinstall some of the apps if they had reset their devices. However, you must remember that the new feature has its own limitations and will work only when you are connected to an active Wi-Fi connection.
Let's look at the 5 ways to Backup and Reset your Android Device:
Backup -> Reset
Go to Settings > Backup & reset. Remember to select the automatic restore if you want to restore your Android Phone, once you are logging in with your Google account.
Back up my Data
In the Backup & reset > Back up my data > Check the On button.
This option will backup all your app data, Wi-fi Passwords, and other settings to the Google servers.
Network Setting reset
In case you want to reset all your Network Settings. There is a way. Instead of having to forget all your Wi-Fi networks, you can Go this section and select Reset. It will reset all your Wi-fi, Bluetooth and Network data.
Set your Back up Account
Setting up your backup account allows you to choose the account that you want to backup all your data.
For Example, if you have logged in from 2-3 Google accounts on your phone, you can choose which of those accounts you want to back up all your App Data and passwords
Check the backup files and reset!
Once you are done with the preliminary steps. Just go to the Factory Data Reset and select "Reset Phone". This will wipe your phone of all data. You should remember that the backup feature is only applicable for apps and app Data.
It will not backup all your data on your storage device. If you have songs on your phone, it is unlikely that your songs will be backed up. The feature is limited only to apps.