1C-Bitrix is a system of web project management, universal software for the creation, support and successful development of corporate websites and online stores.
BEM (Block, Element, Modifier) is a naming convention for classes in HTML and CSS what was developed by Yandex.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
PHP is a general-purpose scripting language used for web development.