# Middleware

This section contains topics about PX4 middleware, including PX4 internal communication mechanisms ([uORB](middleware/uorb)), and between PX4 and offboard systems like companion computers and GCS (e.g. [MAVLink](middleware/mavlink), [uXRCE-DDS](middleware/uxrce_dds)).

:::tip For a detailed overview of the platform architecture see the [Architectural Overview](concept/architecture). :::
