Without getting too technical, it means that Retina display devices show more pixels per square inch, resulting in sharper images.
WPML allows running fully multilingual websites with WordPress, making it easy to translate pages, posts, tags, categories, and more.
Responsive web design is an approach to web design which makes web pages render well on a variety of devices and window or screen sizes.
At ND Graphic Designs, we unanimously recommend WordPress. It is a Content Management System, that allows you to create and publish your content on the web.