Specifically, where a microformat is full XHTML, which I mentioned here previously, a Picoformat is a standard-means for defining markup in small, probably mobile, devices. They are not necessarily in XHTML, and probably not, as XHTML is rather heavy and takes up a lot of screen/memory space. Additionally, writing out long-bits of info take too long on a limited form factor like a phone.
Another solution might be something like Zlango's "picture" dictionary. Using a standard - though rather varied - set of icons, 2 people can "draw out" a message, across language barriers, and convey large amounts of information with minimal clicks. I highly recommend you try out their Zlangulator.