Fastly is a cloud computing services provider. Fastly's cloud platform provides a content delivery network, Internet security services, load balancing, and video & streaming services.
GitHub Pages is a static site hosting service.
Linkedin Sign-In is an authentication system that reduces the burden of login for users, by enabling them to sign in with their Linkedin account.
Pinterest is an image sharing and social media service designed to enable saving and discovery of information.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
Varnish is a reverse caching proxy.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.