AngularJS is a JavaScript-based open-source web application framework led by the Angular Team at Google.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.