Apache is a free and open-source cross-platform web server software.
Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
Headroom.js is a JS widget that allows you to react to the user's scroll. The header slides out of view when scrolling down and slides back in when scrolling up.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Lightbox is small javascript library used to overlay images on top of the current page.
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.
Popper is a positioning engine, its purpose is to calculate the position of an element to make it possible to position it near a given reference element.