Eclipse IDE (Integration Development Environment) is an open source. Hence it is popular for Java application development (Java SE and Java EE) and Android apps. Also supports C/C++, PHP, Python, Perl, and other web project ...

JDK – Java Development Kit is a software development environment used for developing Java applications and applets.  It includes the Java Runtime Environment (JRE), an interpreter/loader (java), a compiler (javac), an archive (jar), a documentation generator ...