Hoon is a strict, higher-order typed functional programming language that compiles itself to Nock. As a result Hoon code is effectively implemented by the interpreter Vere. Programs for the Urbit operating system and kernel, Arvo, are written in Hoon.

The Hoon source file is located in /base/sys/hoon.hoon within your Urbit.

Further Reading

• The Hoon Tutorial: Our guide to learning the Hoon programming language.
  • Lesson 1.1: Setup: How to set up an environment for programming in Hoon.
• Why Hoon?: A blog post that explains why Urbit uses its own programming language.