A BreadcrumbList is an ItemList consisting of a chain of linked Web pages, typically described using at least their URL and their name, and typically ending ...
The important thing about breadcrumb structured data to Google is that it's visible on the page. If it's not entirely visible on the page, this is something ...
A breadcrumb trail on a page indicates the page's position in the site hierarchy, and it may help users understand and explore a site effectively. How to add structured data · Examples · Guidelines · Structured data type definitions
Google uses structured data to understand the content on the page and show that content in a richer appearance in search results, which is called a rich result.