Sleeping apps Vs restrict background data usage

[mun_96]

What is the difference between sleeping apps, deep sleeping apps and restricting background data usage?

If an app is sleeping or deep sleeping, will I still receive notifications?

I am guessing restricting background data usage will stop notifications when you are on data? But you will receive notifications for the app when on WiFi? 

What saves most battery: sleeping apps or restricting background data usage and what is the difference between these 2 settings?

[AndrewL]

@mun_96: Sleeping apps will run in the background only occasionally, and delay updates and notifications. Deep sleeping apps, on the other hand, will never run in the background and will not receive updates or notifications. They'll only work when you open them. Restricting background data usage will stop any background activity for web based apps while you're connected to Mobile Data. If this option is of interest, head to Settings > Connections > Data usage > Data saver > Turn on now.