The java.lang package provides classes that are fundamental to
the design of the JavaTM programming
language.
The java.util.* packages provide support for the event
model, collections framework, date and time facilities, and contains
various utility classes. The java.util.zip and
java.util.jar packages provide support for ZIP file
format and Java Archive (JAR) file formats respectively.
Enhancements
Version 1.3 of the Java 2 SDK offers several enhancements in
the java.lang and java.util.* packages.
See Enhancements for
details.