Java - JDK, JRE, JVM

JDK

Java Development Kit, which provides developer tools like a compiler, debugger, documentation tools (javadoc), and other command-line utilities. The JDK also has a JRE inside of it, so if you install a JDK you can compile your Java code as well as execute it.

JRE

Java Runtime Environment contains all the runtime libraries that your code will be calling and using. The JRE contains the JVM within it, so if you want to run a Java program, all you need to install is the JRE.

JVM

Java Virtual Machine, an interpreter for compiled Java bytecodes and turns it into machine code to be executed on the given system.

bytecode

Java is compiled to what?

Javadoc

The documentation generator in the Java SDK. It extracts documentation comments from Java source files and produces a set of linked HTML files.