Classloaders are primarily a runtime concept that were motivated originally by Java applets. Classloaders enabled loading of one class at a time, which was important in the day of dial-up modems.

Thread context classloaders were introduced in Java 2 Platform, Standard Edition (J2SE). Every Thread has a context classloader associated with it (unless it was created by native code).

As part of Oracle's ongoing project to merge the HotSpot and JRockit codebases, Oracle has announced that they will remove PermGen from the Java 8 version of the HotSpot JVM. The effects of the remova ...