A zerogram is a gram with zero lines. Interesting, huh? Don't ask me what it looks like because I have no idea.
I shall refer to the concept the zerogram stands for as "the nameless".
It has no form. Or perhaps it has all of them... who knows.
Sometimes it is represented by a point or an empty circle (compared to the yin-yang symbol which is represented by a full circle with black and white inside it).
Is there any purpose to talking about the nameless? Well, there is only one: to point out the futility of such talk. The nameless you can talk about is not the true nameless.
Everything we say, write, or relate to in general is represented by duality. We compare one thing to something else, and then we say we have acquired knowledge. However, it is all relative.
We have no concept to relate to the nameless. If we had, it wouldn't really be the nameless anyway.
The nameless is by definition something that doesn't have duality.
And if you laugh at this definition, you will be right. It is made only of words representing concepts of duality: nameless-namefull, is - isn't, definition-indefinition, something-nothing, that - this, not have - have, duality - unity.
So I'll just shut up now.