Newbie question - erasing SSD erases OS?

[Tenashus1]

I think this is true, correct? So then if everything is erased how is OS restored on machine for later use?

 

[simonsi]

Yes erasing the SSD (or HDD) completely will erase the OS.

How you recover or reinstall depends on the age of your machine, you might have internet recovery or need recovery disks. Best is to download a copy of the installer and create a bootable USB drive using DiskmakerX

 

[T5BRICK]

I think this is true, correct? So then if everything is erased how is OS restored on machine for later use?

Internet recovery.

https://support.apple.com/en-us/HT201314