> ## Documentation Index
> Fetch the complete documentation index at: https://aletyx.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# What is DMN?
> DMN (Decision Model and Notation) is an OMG standard for modeling business decisions visually with decision tables and FEEL - portable and directly executable.
**DMN (Decision Model and Notation)** is an [OMG](https://www.omg.org/dmn/)
standard for modeling business decisions visually. Instead of burying logic in
code, you describe **what the decision is, what inputs it needs, and how the
inputs map to outcomes** — using decision tables and boxed expressions written in
FEEL (Friendly Enough Expression Language).
Because it is a portable, vendor-neutral standard, the same DMN model can be read
by business analysts, validated by compliance teams, and executed directly by an
engine — no translation step between the diagram and the running logic.
A DMN model usually has two parts: a **Decision Requirements Diagram (DRD)** that
shows which inputs feed which decisions, and a **decision table** that spells out
the rules.
If you can read a spreadsheet, you can read the decision table: **conditions on
the left, outcomes on the right**.
## Where to go next
Learn the building blocks — decision tables, DRDs, and FEEL — from the ground up.
Build and run an executable DMN model directly in the Aletyx Playground.
Walk through a worked example, from inputs to a decision table.
Go deeper with multi-decision DRDs and more expressive FEEL.
Look up FEEL syntax, reserved words, and expression details.
Package and deploy decision models as runnable services.