Plugins are pieces of code created with the purpose of expanding the functionalities of a software, in this case of WordPress. There are literally thousands of WordPress plugins already created, solving a wide range of problems and needs.
WordPress Themes are files that work together to create the design and functionality of a WordPress site. Each Theme may be different, offering many choices for site owners to instantly change their website look.
Dragon Code is a Telnet Talker base code.
A talker is a chat system that people use to talk to each other over the Internet. Dating back to the 1980s, they were a predecessor of instant messaging.