# Fundamentals - [Getting started](https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals/getting-started.md) - [Router configuration](https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals/router-configuration.md): Learn about configuring the Router. - [Defining routes](https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals/configuring-routes.md): Learn about configuring routes in Router. - [Child routing playbook](https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals/child-routing.md): Build deeply nested navigation trees with Aurelia's router, including layouts, sibling viewports, and relative navigation. - [Route parameters](https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals/route-parameters.md): Declare, read, and validate route parameters in Aurelia's router, including required, optional, wildcard, and constrained segments. - [Viewports](https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals/viewports.md): Learn about viewports in Aurelia router and how to create complex layouts with hierarchical and sibling viewports. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.aurelia.io/getting-to-know-aurelia/aurelia-router/fundamentals.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.