Apache is a free and open-source cross-platform web server software.
Google Maps is a web mapping service. It offers satellite imagery, aerial photography, street maps, 360° interactive panoramic views of streets, real-time traffic conditions, and route planning for traveling by foot, car, bicycle and air, or public transportation.
Gravatar is a service for providing globally unique avatars.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Site Kit is a one-stop solution for WordPress users to use everything Google has to offer to make them successful on the web.
Slider Revolution is a flexible and highly customisable slider.
W3 Total Cache (W3TC) improves the SEO and increases website performance and reducing load times by leveraging features like content delivery network (CDN) integration and the latest best practices.