HTML, HTML5, XHTML, XML, CSS, CSS 3, XUL
W3C Standards

Testing Utilities

Selenium, JUnit, HP LoadRunner, Grinder, NeoLoad, ...
Reporting Libraries

Highcharts, JasperReport, JFreeChart, PDF.js, BIRT
Java EE Compliance

Java EE, Jakarta EE, Servlet 2.3/2.4/+, Portlet, JSP, JSF, JPA, EJB, JDO, CDI, JDK 8+
Supporting Frameworks

Spring, ZK Spring, Grails, ZKGrails, Struts, Tiles, Liferay, JetSpeed 2, Hibernate, Oracle TopLink, Seam, Seasar...
Ajax UI Libraries

jQuery, Flash, CKEditor, SIMILE Timeline, SIMILE Timplot, Google Maps
Scripting Support

Java, Groovy, JavaScript, Ruby, Python, PHP, Scala, Clojure
Browser Support

Chrome, Firefox, IE, Edge, Safari, Mobile Safari, Opera, Webkit, Konqueror, Mozilla
Mobile Platform Support

iPad, iPhone, Android, Blackberry, JavaME enabled mobile devices
Web Servers

Apache Tomcat, IBM WebSphere, IBM WebSphere Process Server, IBM WebSphere Portal, SAP NetWeaver, Spring tc Server, jBoss Application Server, BEA WebLogic, Oracle OC4J, Sun GlassFish, Jetty, Google App Engine, among other application server compliant with servlet 2.3 specification and above.