Apache Derby is a subproject of the Apache DB project.
You can find Derby on the web at:

http://db.apache.org/derby/

Apache Derby releases can be downloaded from the following page:

http://db.apache.org/derby/derby_downloads.html

Derby is a pure Java, standards-based relational database engine.
Derby aims to be an easy to use solution for data management for
software developers with zero administration for end users.

The 10.1 release includes a new open source network client driver, as
well as a number of other new features and enhancements:

    * Support for J2ME/CDC/Foundation with JSR-169 JDBC subset
    * Online compress functionality for reclaiming disk space during
operation
    * XA support for Network Server
    * Increased identifier lengths to 128 characters for all identifiers
    * Added SQL: INTERSECT and EXCEPT
    * Added SQL: SYNONYM
    * JDBC Updatable Result Sets
    * ORDER by expressions
    * Allow insertions into an identity column
    * Support for explicit Java method signature in function and
procedure definitions


See the CHANGES file for a list of changes in the lastest snapshot or release distribution of 10.1.

Cryptographic Software Notice
-----------------------------
This distribution includes cryptographic software.  The country in
which you currently reside may have restrictions on the import,
possession, use, and/or re-export to another country, of
encryption software.  BEFORE using any encryption software, please
check your country's laws, regulations and policies concerning the
import, possession, or use, and re-export of encryption software, to
see if this is permitted.  See http://www.wassenaar.org/ for more
information.

The U.S. Government Department of Commerce, Bureau of Industry and
Security (BIS), has classified this software as Export Commodity
Control Number (ECCN) 5D002.C.1, which includes information security
software using or performing cryptographic functions with asymmetric
algorithms.  The form and manner of this Apache Software Foundation
distribution makes it eligible for export under the License Exception
ENC Technology Software Unrestricted (TSU) exception (see the BIS
Export Administration Regulations, Section 740.13) for both object
code and source code.

The following provides more details on the included cryptographic
software:

  Apache Derby interfaces with the Java Cryptography Extension (JCE) API
  to provide

   - Full on-disk encryption of database files
   - Storage and authentication of user passwords stored in the database
   - User and password encryption over a network

  Apache Derby does not include any implementation of JCE.