The language is made up of two abstract elements, which we call "flow-function" and "IKO". Every Obyx document needs to use one of the four flow-functions as a root element. In many cases, this will be an instruction. The term "IKO" stands for Input-Key-Output, and represents the parameters that will be given to any flow-function.
Alongside the Obyx language itself are OSI objects, which may also be evaluated by the Obyx engine. OSI objects handle transactions such as emails and http requests.