AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
Java is a class-based, object-oriented programming language that is designed to have as few implementation dependencies as possible.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.