AddEvent is used to Add to Calendar and event tools for websites and newsletters.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Google PageSpeed is a family of tools designed to help websites performance optimisations.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
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.