JAMStack (JavaScript, APIs, Markup) is a way to build website created & promoted by the company Netlify. From what I understand all three things shown in this course are more or less JAMStack (WordPress is not a part of the JAMStack but I’ve seen WordPress REST API called “headless WordPress” and classified as JAMStack CMS 🤷)

You might find jamstack.org and jamstack.wtf interesting for your own learning or for better interacting with web developers you might hire.