cdnjs is a free distributed JS library delivery service.
DDoS-Guard is a Russian Internet infrastructure company which provides DDoS protection, content delivery network services, and web hosting services.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Tally is the simplest way to create free forms & surveys. Create any type of form in seconds, without knowing how to code, and for free.
Tilda is a web design tool.
VK is a Russian online social media and social networking service.