Calendly is an app for scheduling appointments, meetings, and events.
Internet Information Services (IIS) is an extensible web server software created by Microsoft for use with the Windows NT family.
Open Graph is a protocol that is used to integrate any web page into the social graph.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
SweetAlert is a JavaScript library that provides alternative alert and modal dialog boxes for web applications, with customisable features, aiming to improve the user interface of the default browser dialogs.
Unpkg is a content delivery network for everything on npm.