[html] HTML IF Statement

I just wanna know how to do an if-statement in simple HTML. Like the [if IE6] thingy

I'd like to do something like this

[IF 5>6]

How's the syntax? I can't seem to find anything but [If!IE6] and things like that, is that even possible?

Thanks a lot

Edit: I want to compare just scalar numbers, cause I have a dynamically created HTML. For example [If 4 == 6]. I DON'T WANT TO CHECK IE VERSIONS.