Detailed answer
Use a labeled nav with a list representing the hierarchy.
Earlier levels can be links; the current item can use aria-current=page. Keep the wording useful without depending solely on separator graphics. Breadcrumbs describe location in the content structure rather than a history of every page the user visited.
Example
<nav aria-label="Breadcrumb"><ol><li><a href="/">Home</a></li><li><a href="/html/">HTML</a></li><li aria-current="page">Forms</li></ol></nav>
Understanding the behavior
Breadcrumbs describe a page's place in a hierarchy rather than the visitor's complete browsing history. Put them in a distinctly named navigation region and use meaningful destination labels. The current page can be text or a clearly identified link.
Practical implementation notes
Check that every parent link leads to a real, useful collection page. Any BreadcrumbList markup should match the visible hierarchy instead of introducing categories that users cannot actually navigate to.
How to check it
Read its ordered items and compare them with the actual site hierarchy.
Expected result
It describes Home, HTML, and the current lesson rather than browsing history.
Watch out: Do not confuse the site hierarchy with browser history.
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