ACT will run on any machine that has a recent version of Java. Most of the development has been done using JDK v1.1.7 and v1.1.8, but any version better than v1.1.1 is sufficient for running ACT on UNIX. (Early versions of v1.1 have some bugs, so later is better.) Version 1.2 or better is needed on Windows. Please note that the version of Java that comes with Netscape and Internet Explorer is not sufficient to run ACT. See the section called Getting and Installing ACT for details on how to get Java.