Rich snippets, also known as rich results, are a feature on SERPs that displays extra details about the search result. These rich results are displayed when webmasters include a special code, called structured schema or schema markup, within a web page’s HTML.
Newcomers to SEO sometimes confuse on-page vs. off-page SEO, even though they’re completely different things. While they’re both fundamental SEO elements needed boost your website’s search rankings, they do this in different ways.
On-page optimization is one of the pillars of search engine optimization; its goal is to optimize the elements on your web pages to help them rank higher on search engine results, thereby attracting more organic traffic.