Do I have the most current release of Java?

Apple's Developer technote here:

Technical Note TN2110: Identifying Java on OS X

Explains what are all the Mac OS X releases for Java, and how to determine if you have the that version. If you don't check Apple - Support - Downloads to see if you can run that update on your machine.

Note, starting with Mac OS X 10.7, Oracle at http://www.java.com/ maintained Java.  Use that link to verify your Java version if your operating system is more current than 10.7.

Note: Java releases should not be confused with versions of Java released on Microsoft platforms which require ActiveX as a plugin.   Both Microsoft and Netscape have a similarly named addon called Jscript and Javascript respectively which have been used to extend programs on webpages that does not use Oracle's Java, even though the name is similar.