When your blocked, your editing will not be saved. When you press the SAVE button, it will say that you've been blocked and will say it on the Wiki Notification thing when you create a page. It says whose blocked you, your IP ADDRESS and that stuff
Local means that your only blocked on that WIKI. Not other wikis. You cannot edit or post or vote in polls when you want to
Global is when FANDOM blocks your account from ALL WIKIS so you cannot login to your account (MAYBE) but it depends on what you've done for a globally action ro happen to you