Apache is a free and open-source cross-platform web server software.
Express is a web application framework for Node.js, released as free and open-source software under the MIT License. It is designed for building web applications and APIs.
OpenSSL is a software library for applications that secure communications over computer networks against eavesdropping or need to identify the party at the other end.
Unix is a family of multitasking, multiuser computer operating systems.