cdnjs is a free distributed JS library delivery service.
Choices.js is a lightweight, configurable select box/text input plugin.
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.
OpenResty is a web platform based on nginx which can run Lua scripts using its LuaJIT engine.
Unpkg is a content delivery network for everything on npm.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.