JDK means Java Development (tool) Kit
JDK is therefore an SDK specifically for Java development. The first JDKs were released in the mid-years 90, in the time that many Java applets were still used. Version 1 of the JDK had tools for developing applets and applications for the Sun Solaris, Windows and Macintosh systems. Java has been widely used and in 2006, Sun Java has released a GNU license, making it free software.
Installing JDK [YouTube] O2cQLSMQAC0 [/youtube]