Structured info is extra directly to a website page's HTML markup. Search engines like google and yahoo use structured facts to generate rich snippets, which can be smaller pieces of knowledge that could then surface in search engine results. The start date and start time from the event in ISO-8601 https://addons.prestashop.com/pt/seo-referenciamento-natural/31857-rich-snippets-automaticos-json-ld-opengraph-seo.html