What does memorialize mean? My father died some years ago and his account is still there, so I'm curious.

The most important thing it does is remove them from suggest a friend requests list which can be very disturbing to receive.

'John wants to connect with you', Oh that's cool, wtf?! John's dead?!

According to [0]

>Depending on the privacy settings of the deceased person's account, friends can share memories on the memorialized timeline

I'd love to know which Privacy Settings control this ability, it's interesting they don't specifically call out the relevant option.

[0] https://www.facebook.com/help/www/103897939701143?rdrhc

It's probably "allow friends to post on my wall" (or anyone).