Lower Anchors and Tethers for Children (LATCH) is a standard adopted by the NHTSA in 2002 for child seat anchor points. It labels what is required of a LATCH point, and that all vehicles sold in the US after the standard's adoption must have proper LATCH points. Nothing really major, expensive, or groundbreaking was added to safety design by this, but it drastically improved child safety in accidents where a carseat was involved.
ZJs are, of course, pre-LATCH, so they have different methods of security. Early ZJs sometimes have 4 rear seatbelt plugs to accept a wider child seat in the middle of the bench, as at that time, the lap belt was the only securing device on a child seat. Later ZJs did away with it, as it cost money to have, and wasn't a popular option because the normal plug was sufficient. Thus the 4-buckle rear seat is pretty rare.
1998 Grand Cherokee 5.9 Limited
2016 Wrangler Unlimited Sahara Edition
Signature rules are dumb