This is the perfect opportunity to explain binomial nomenclature, since this is the way many dinosaurs are referred to and people always mess it up, especially with T. rex. If you ever notice, in science they use funny Greek and Latin names
that nobody understands to name organisms. The animal is referred to by
its genus and species. It is written like this:
"Genus species" or "G. species" for short.
Also, a subspecies name can be added:
"Genus species subspecies" or "G. s. subspecies" for short.
The genus name is capitalized, and the species (and subspecies) are left
lowercase. A period is used after the abbreviated genus and species
names when applicable. Genus, species, and subspecies names should be
italicized even when abbreviated. Though italicizing on the forums is a
pain since Ctrl+I doesn't seem to work, so it's probably better to
forget that. Anyway, the binomial nomenclature of T. rex is Tyrannosaurus rex
(the genus meaning "tyrant lizard" and the species meaning "king," thus
making "king of the tyrant lizards") and can be abbreviated as T. rex. Only T. rex is correct; T-Rex, T. Rex, T-rex, t. rex, and t-rex are all incorrect.
Here are some more examples (no dinosaur examples; don't know any of the top of my head):
American black bear = Ursus americanus -> U. americanus
eastern black bear = Ursus americanus americanus -> U. a. americanus
moose (elk in Europe) = Alces alces -> A. alces
Shiras moose = Alces alces shirasi -> A. a. shirasi
tiger = Panthera tigris -> P. tigris
Caspian tiger = Panthera tigris virgata -> P. t. virgata
You get the idea. Hopefully some of you will now get this right. I doubt it though.
Fun fact: while in zoology it is very common for animals to have the same genus and species name and sometimes even subspecies name (such as the lowland gotilla, Gorilla gorilla gorilla), it is for some reason strictly forbidden in botany, though there are plants where the genus and species name mean the same but with one and Greek and the other in Latin or even with the genus and species being almost the same word but with spelling variations.