- [HTTP Server](http://httpd.apache.org/ "Apache Web Server (httpd)")
- [Abdera](http://abdera.apache.org/ "Atom Publishing Protocol Implementation")
- [Accumulo](http://accumulo.apache.org/ "Sorted, distributed key/value store")
- [ACE](http://ace.apache.org/ "Centralized life cycle management and deployment of OSGi based and related modular software artifacts for distribution.")
- [ActiveMQ](http://activemq.apache.org/ "Distributed Messaging System")
- [Airavata](http://airavata.apache.org/ "Workflow and Computational Job Management Middleware")
- [Ant](http://ant.apache.org/ "Java-based build tool")
- [APR](http://apr.apache.org/ "Apache Portable Runtime libraries")
- [Archiva](http://archiva.apache.org/ "Build Artifact Repository Manager")
- [Aries](http://aries.apache.org/ "Enterprise OSGi application programming model")
- [Avro](http://avro.apache.org/ "A Serialization System")
- [Axis](http://axis.apache.org/ "Java SOAP Engine")
- [Buildr](http://buildr.apache.org/ "Simple and intuitive build system for Java applications")
- [BVal](http://bval.apache.org/ "Apache BVal: JSR-303 Bean Validation Implementation and Extensions")
- [Camel](http://camel.apache.org/ "Spring based Integration Framework which implements the Enterprise Integration Patterns")
- [Cassandra](http://cassandra.apache.org/ "Highly scalable second-generation distributed database")
- [Cayenne](http://cayenne.apache.org/ "User-friendly Java ORM with Tools")
- [Chemistry](http://chemistry.apache.org/ "CMIS (Content Managment Interoperability Services) Clients and Servers")
- [Click](http://click.apache.org/ "User-friendly page and component oriented web framework")
- [Cocoon](http://cocoon.apache.org/ "Web development framework: separation of concerns, component-based")
- [Commons](http://commons.apache.org/ "Reusable Java components")
- [Continuum](http://continuum.apache.org/ "Continuous Integration and Build Server")
- [CouchDB](http://couchdb.apache.org/ "RESTful document database")
- [Creadur](http://creadur.apache.org/ "Comprehension and auditing of software distributions")
- [CXF](http://cxf.apache.org/ "Service Framework")
- [DB](http://db.apache.org/ "Database access")
- [Deltacloud](http://deltacloud.apache.org/ "RESTful cloud management interface")
- [Directory](http://directory.apache.org/ "Apache Directory Server")
- [Empire-db](http://empire-db.apache.org/ "Relational Data Persistence")
- [ESME](http://esme.apache.org/ "Enterprise Social Messaging Environment")
- [Felix](http://felix.apache.org/ "OSGi Framework and components.")
- [Flume](http://flume.apache.org/ "A reliable service for efficiently collecting, aggregating, and moving large amounts of log data")
- [Forrest](http://forrest.apache.org/ "Aggregated multi-channel documentation, separation of concerns")
- [Geronimo](http://geronimo.apache.org/ "Java2, Enterprise Edition (J2EE) container")
- [Gora](http://gora.apache.org/ "ORM framework for column stores such as Apache HBase and Apache Cassandra with a specific focus on Hadoop")
- [Gump](http://gump.apache.org/ "Continuous integration of open source projects")
- [Hadoop](http://hadoop.apache.org/ "Distributed computing platform")
- [Hama](http://hama.apache.org/ "a Bulk Synchronous Parallel computing framework on top of Hadoop")
- [HBase](http://hbase.apache.org/ "Hadoop Database")
- [Hive](http://hive.apache.org/ "Data warehouse infrastructure using the Hadoop Database")
- [HttpComponents](http://hc.apache.org/ "Java toolset of low level HTTP components")
- [Jackrabbit](http://jackrabbit.apache.org/ "Content Repository for Java")
- [James](http://james.apache.org/ "Java Apache Mail Enterprise Server")
- [Jena](http://jena.apache.org/ "Java framework for building Semantic Web applications")
- [JMeter](http://jmeter.apache.org/ "Java performance and functional testing")
- [jUDDI](http://juddi.apache.org/ "Java implementation of the Universal Description, Discovery, and Integration specification")
- [Karaf](http://karaf.apache.org/ "Server-side OSGi distribution")
- [Lenya](http://lenya.apache.org/ "Content Management System")
- [Libcloud](http://libcloud.apache.org/ "Unified interface to the cloud")
- [Logging](http://logging.apache.org/ "Cross-language logging services")
- [Lucene](http://lucene.apache.org/ "Search engine library")
- [Lucy](http://lucy.apache.org/ "Search engine library for dynamic languages")
- [Mahout](http://mahout.apache.org/ "Scalable machine learning library")
- [ManifoldCF](http://manifoldcf.apache.org/ "Framework for connecting source content repositories to target repositories or indexes.")
- [Maven](http://maven.apache.org/ "Java project management and comprehension tools")
- [MINA](http://mina.apache.org/ "Multipurpose Infrastructure for Network Application")
- [MRUnit](http://mrunit.apache.org/ "Java library that helps developers unit test Apache Hadoop map reduce jobs")
- [MyFaces](http://myfaces.apache.org/ "JavaServer(tm) Faces implementation and components")
- [Nutch](http://nutch.apache.org/ "Open Source Web Search Software")
- [ODE](http://ode.apache.org/ "Orchestration Director Engine: Business Process Management (BPM), Process Orchestration and Workflow through service composition.")
- [OODT](http://oodt.apache.org/ "Object Oriented Data Technology (middleware metadata)")
- [OFBiz](http://ofbiz.apache.org/ "Open for Business: enterprise automation software")
- [Oozie](http://oozie.apache.org/ "A workflow scheduler system to manage Apache Hadoop jobs.")
- [OpenEJB](http://openejb.apache.org/ "OpenEJB: a modular, configurable, and extendable EJB Container System and Server")
- [OpenJPA](http://openjpa.apache.org/ "OpenJPA: Object Relational Mapping for Java")
- [OpenNLP](http://opennlp.apache.org/ "Machine learning based toolkit for the processing of natural language text")
- [OpenWebBeans](http://openwebbeans.apache.org/ "OpenWebBeans: JSR-299 Context and Dependency Injection for Java EE Platform Implementation")
- [PDFBox](http://pdfbox.apache.org/ "Java library for working with PDF documents")
- [Perl](http://perl.apache.org/ "Dynamic websites using Perl")
- [Pig](http://pig.apache.org/ "Platform for analyzing large data sets")
- [Pivot](http://pivot.apache.org/ "Rich Internet applications in Java")
- [POI](http://poi.apache.org/ "Java API for OLE 2 Compound and OOXML Documents")
- [Portals](http://portals.apache.org/ "Portal technology")
- [Qpid](http://qpid.apache.org/ "Multiple language implementation of the latest Advanced Message Queuing Protocol (AMQP)")
- [Rave](http://rave.apache.org/ "Web and social mashup engine")
- [River](http://river.apache.org/ "Jini service oriented architecture")
- [Roller](http://roller.apache.org/ "Java blog server")
- [Santuario](http://santuario.apache.org/ "XML Security in Java and C++")
- [ServiceMix](http://servicemix.apache.org/ "Enterprise Service Bus")
- [Shindig](http://shindig.apache.org/ "Opensocial Reference Implementation")
- [Shiro](http://shiro.apache.org/ "Powerful and easy-to-use application security framework")
- [Sling](http://sling.apache.org/ "Web Framework for JCR Content Repositories")
- [SpamAssassin](http://spamassassin.apache.org/ "Mail filter to identify spam")
- [STDCXX](http://stdcxx.apache.org/ "Apache C++ Standard Library")
- [Sqoop](http://sqoop.apache.org/ "Bulk Data Transfer for Hadoop and Structured Datastores")
- [Struts](http://struts.apache.org/ "Model 2 framework for building Java web applications")
- [Subversion](http://subversion.apache.org/ "Version Control")
- [Synapse](http://synapse.apache.org/ "Enterprise Service Bus and Mediation Framework")
- [Tapestry](http://tapestry.apache.org/ "Component-based Java Web Application Framework")
- [Tcl](http://tcl.apache.org/ "Dynamic websites using TCL")
- [Thrift](http://thrift.apache.org/ "Framework for scalable cross-language services development")
- [Tika](http://tika.apache.org "Content Analysis and Detection Toolkit")
- [Tiles](http://tiles.apache.org/ "A templating framework for web application user interfaces")
- [Tomcat](http://tomcat.apache.org/ "A Java Servlet and JSP Container")
- [Traffic Server](http://trafficserver.apache.org/ "A fast, scalable and extensible HTTP/1.1 compliant caching proxy server")
- [Turbine](http://turbine.apache.org/ "A Java Servlet Web Application Framework and associated component library")
- [Tuscany](http://tuscany.apache.org/ "An SCA based Service Composition Framework")
- [UIMA](http://uima.apache.org/ "Framework and annotators for unstructured information analysis")
- [Velocity](http://velocity.apache.org/ "A Java Templating Engine")
- [Web Services](http://ws.apache.org/)
- [Whirr](http://whirr.apache.org/ "Libraries for running Cloud Services")
- [Wicket](http://wicket.apache.org/ "Component-based Java Web Application Framework.")
- [Xalan](http://xalan.apache.org/ "XSLT processors in Java and C++")
- [Xerces](http://xerces.apache.org/ "XML parsers in Java, C++ and Perl")
- [XMLBeans](http://xmlbeans.apache.org/ "XML-Java binding tool")
- [XML Graphics](http://xmlgraphics.apache.org/ "Conversion from XML to graphical output")
- [ZooKeeper](http://zookeeper.apache.org/ "Centralized service for maintaining configuration information")