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

# Concepts

This section covers the core concepts and architecture of Rumi Core - the foundational runtime for building microservice-based applications.

## Topics

* [Introduction](/rumi-core/concepts/introduction.md)
* [What is Rumi Core](/rumi-core/concepts/what-is-rumi-core.md)
* [Messaging Model](/rumi-core/concepts/messaging-model.md)
* [Microservice Architecture](/rumi-core/concepts/microservice-architecture.md)
* [Microservice Operation](/rumi-core/concepts/microservice-operation.md)
* [Consensus Models](/rumi-core/concepts/consensus-models.md)
* [Transactions](/rumi-core/concepts/transactions.md)
* [Threading Model](/rumi-core/concepts/threading-model.md)
* [Discovery Model](/rumi-core/concepts/discovery-model.md)
* [Operating Model](/rumi-core/concepts/operating-model.md)