Calendly is an app for scheduling appointments, meetings, and events.
cdnjs is a free distributed JS library delivery service.
Firebase is a Google-backed application development software that enables developers to develop iOS, Android and Web apps.
Google Cloud Trace is a distributed tracing system that collects latency data from applications and displays it in the Google Cloud Console.
Google Sign-In is a secure authentication system that reduces the burden of login for users, by enabling them to sign in with their Google account.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
HTTP/3 is the third major version of the Hypertext Transfer Protocol used to exchange information on the World Wide Web.
Open Graph is a protocol that is used to integrate any web page into the social graph.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.