In order to use the OT, it should only be necessary that the computer in question has Java installed. Most computers have Java pre-installed, but if this is not the case, the latest version of Java (also known as the Java Runtime Environment or JRE) should be downloaded from http://java.com. Regarding the version of Java, it is absolutely essential that version 6 of Java (also known as JAVA SE 6) be installed, although Java 7 also seems to work without any problems. The currently installed version can be checked by typing java -version on the command line, the output of which should look something like this:
java version "1.7.0_13" Java(TM) SE Runtime Environment (build 1.7.0_13-b20) Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)The _13 in this particular example refers to the patch release of the installation and should increment every time the Java installation is updated. Patch releases do appear intermittently and should usually be installed. When reporting a problem with the OT, the full version number including the patch release should be reported.