Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
Hugo is an open-source static site generator written in Go.
JSDelivr is a free public CDN for open-source projects. It can serve web files directly from the npm registry and GitHub repositories without any configuration.
Popper is a positioning engine, its purpose is to calculate the position of an element to make it possible to position it near a given reference element.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.