Not all operating systems like the '<' and '>' in the object names

I'm aware there's some issue of OS not liking such object names, but I don't get it.

For example, [<] and [>] are vanilla objects, don't they load in every OS?

And what does it mean? Do these objects not load on every system even when declared?

I know it loads on MAC OS, what I use, when declared anyway

But I also know that if you try and load [<~] and [>~] from zexy you need a [hexloader] object. Don't know why it doesn't load without it.

cheers