There're two numbers that provide identification from a build to another, version system is designed to be used by all applications and the System itself, to manage retro-compatibility of a system without big modification of the internal structure while updating the system.
The two numbers are splited by a dot. The second number represents the amount of commit when this specific build was released.
The first number is mostly abstract (it represents the major version), it means that we're not classifying any version from Kot but the target of the life thread of Kot's development, and what Kot achieve.
"waterfall" (aka "0") defines that Kot is currently making its foundation and its goal is to provide a stable system for building the next part of Kot as well.
"snowball" (aka "1") defines that Kot is no more making its foundation and its new goal is to provide a system to be usable from human, without needing the help from another external system.
Right now, there's no other defined version of Kot in this document, because we're not even in the first major version.
For instance, the current version of Kot when this document was written is: "0.542"