The pathya vat is Cambodian in origin, and as with most Cambodian forms was meant to be chanted or sung. It has four lines of four syllables each, with the second and third lines rhyming. That's all there is to it.
Longer poems are made by chaining them together, with the last line of each rhyming with the second and third lines of the next.
xxxx
xxxa
xxxa
xxxb
xxxx
xxxb
xxxb
xxxc
and so on. The beauty of the Pathya Vat is its minimalist form, and the fact that you can make it as long, or as short, as you wish.
As you can see by the length of my example, I rather enjoyed this form. :-)
JOURNEY
I walk the path
that others shun,
my story’s spun
of mist and dreams.
This way is not
quite what it seems,
and yet it teems
with joy for me.
And if the world
does not agree
I still am free
to choose my way.
When from my path
I chance to stray
I may delay
but not for long.
Where will it end?
Where I am strong,
where I belong,
when I am home.