Glass does not break when mined, emits light, only players can pass through, and some secret glass.
A special kind of glass that emits light
A glass that lets only players pass through, mobs cant
All glasses are almost indestructible.
sample of player passing through the ethereal glass
All mobs cannot pass ethereal glass
different type of glass where one side is camouflage
camouflage glass with cobblestone side