> For the complete documentation index, see [llms.txt](https://energytransition.gitbook.io/esdl/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://energytransition.gitbook.io/esdl/esdl-concepts.md).

# ESDL concepts

This chapter describes the ESDL concept. The following topics will be covered:

* [Design principles](/esdl/esdl-concepts/design-principles.md): the general design principles behind the language: capabilities and aggregation
* [Energy System structure](/esdl/esdl-concepts/energy-system-structure.md): the high level structure of an EnergySystem description
* [Data types](/esdl/esdl-concepts/data-types.md): the most important data types in the language: EnergySystem, Instance, Potential, Area, Asset, EnergyAsset, Port, Profile
* [ESDL model](/esdl/esdl-concepts/esdl-model.md): a visualization of the ESDL model