BEM (Block, Element, Modifier) is a naming convention for classes in HTML and CSS what was developed by Yandex.
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.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.
SendPulse is an email marketing platform with additional channels: SMS, web push notifications, Facebook and WhatsApp chatbots.
VK is a Russian online social media and social networking service.