HomeRun was designed to work in as many computer environments as possible. Since it is written in Java, it ought to operate on any operating system that supports a 1.5 Java runtime: and this includes Microsoft Windows 98 through Vista, Linux (most recent distributions), Apple Mac OS, and Sun Solaris 8 though 10. It should also be very modest in terms of compute resources: almost any computer made within the last five years will have ample CPU, memory, disk, etc
You can operate a very useful HomeRun system without using any conventional automation hardware, but many people will have or expect to acquire HA equipment for use with HomeRun. Currently HomeRun supports both the X10 and Insteon 'standards'. A 'standard' in this context means one or more communication protocols, and a set of products using these protocols. Software protocol support almost always requires some additional hardware that bridges between the software program and the physical communication channel(s). These devices go by various names, and use various standard computer interfaces. HomeRun supports:
CM11Acomputer interface: connects to the computer's RS-232 serial port.
PowerLinc Serial Controller- connects to the computer's RS-232 serial port.
Note that USB-based bridges are not supported.
The best way to learn about the system is to download and use it. Most client applications have a fairly extensive set of help files, including general explanation, task-oriented instructions and the like.
If you prefer getting the high-level picture first, consult the user manual, which you may also refer to as needed.
Also, be sure to follow the packages link (also above), which includes comprehensive documentation for HomeRun packages, which are where most of its capabilities live.
Like most open source projects, the primary means of support is the community that uses and develops it. If you find a defect in the software, log a bug report (look for the Submit New link), after making sure that it has not already been reported. If you need assistance in understanding how the software works, visit the forums, especially help.