reStructuredText is an easy-to-read, what-you-see-is-what-you-get plaintext markup syntax and parser system. It's inspired by StructuredText and others but is more formal, better documented, more actively developed, and more complicated.

Acronyms in use include many permutations of the letters r, e, s and t. I use RST.

RST is the default markup syntax on a fresh Zwiki install.

Other notes:

RSTTests.