Google Reader is a content application and platform provided by Google that is an aggregator of content served by web feeds. It was created in early 2005 by Google engineer Chris Wetherell and launched on October 7, 2005, through Google Labs. Google Reader grew in popularity to support a number of apps which use it as a platform for serving news and information to people. On March 13, 2013, Google announced that Google Reader will be closed on July 1, 2013, due to declining use.
Java is a general-purpose, concurrent, class-based, object-oriented computer programming language that is specifically designed to have as few implementation dependencies as possible. It is intended to let application developers "write once, run anywhere" (WORA), meaning that code that runs on one platform does not need to be recompiled to run on another.
An open source license is a copyright license for computer software that allows the source code to be freely, that is by anyone for any purpose, used, modified and shared. This allows end users to review and modify the source code for their own customization, curiosity or troubleshooting needs.