cdnjs is a free distributed JS library delivery service.
Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Pinterest is an image sharing and social media service designed to enable saving and discovery of information.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.