Standard Particle Shaders Material Inspector window reference for the Built-In Render Pipeline

Particle System custom vertex streams in the Built-In Render Pipeline

Custom data streams in Particle Systems in the Built-In Render Pipeline

Important: The Built-In Render Pipeline is deprecated and will be made obsolete in a future release.
It remains supported, including bug fixes and maintenance, through the full Unity 6.7 LTS lifecycle.
For more information on migration, refer to Migrating from the Built-In Render Pipeline to the Universal Render Pipeline and Render pipeline feature comparison.

Resources on implementing custom data streams in your Particle System particle rendering shader setup.

Property	Function
Particle System vertex streams	Understand how custom vertex streams can configure your Particle Systems to pass a wider range of data into your custom Shaders.
Example of Particle System Standard Shader custom vertex streams	View an example of custom vertex streams implemented with a Standard Shader.
Example of Particle System Surface Shader custom vertex streams	View an example of custom vertex streams implemented with a Surface Shader.
Define custom data formats for particles	Apply custom data formats to individual particles.

Standard Particle Shaders Material Inspector window reference for the Built-In Render Pipeline

Particle System custom vertex streams in the Built-In Render Pipeline

Unity Manual