The Facets can be used to customize your presentation layer and provide your users with a Guided Search that lets them drill down into their search results.
This tutorial explains the approach to configure the facets in Adobe Search & Promote.
The website users can narrow down their search results with enabled facets, there are two types of facets in Search and Promote — Static and Dynamic, we are going to use Static facets for this tutorial.
The facet is defined based on the metadata, as a first step, define a metadata e.g productType
The meta data’s can be managed from Settings →Metadata →Definitions