0 is used as a Valid Process identifier. It is used as the PPID for /etc/init that starts everything on the server. The PPID Is the Parent Process Identifier. The Parent Process is Process 0, or the System Startup Process. All processes spawn from this PPID. PID 1 is /etc/init which starts up everything else.
PID stands for Process Identifier, a uniquely assigned integer that identifies a process in the operating system. In any system, applications use PID to identify the process uniquely. Also, it is used in diagnosing the problems with the process in Multi-Tasking systems.
There is no traditional 'execute' command in Unix.
Use the 'PS' (process status) command to find out the name of the executable file for a process. If you use the long form and you know the process id, try: PS -p process-id -l or PS -p process-id -f
It is possible to use BSD software on Unix systems. It is possible but many do not and they use other softwares on Unix systems beside the BSD software.
Unix can be used on a large number of mainframes, servers, and workstations. If you would like to use a certified UNIX system on commodity hardware, Solaris 10 can be downloaded free of charge for non-commercial use.
Yes, quite a bit of companies and users use unix.
Generally any process may be terminated by sending the appropriate signal to it. The command to send signals to a process is called 'kill', and the various signals you can use are identified by 'kill -l' or by 'man kill'
A "process" is a program. In multitasking environments such as Unix or Windows - in fact, in most modern operating systems - the computer can run multiple processes at the same time. Note that not all of such processes need to have a visible window - some can be hidden from the user, until you use a special tool or command to list the processes.
You should be able to download the Unix Services for Windows, version 3.5, from Microsoft (free). There are other shell emulators that are available for Windows, which would allow you to use Unix type shell scripting without installing any additional OS. Your question about "virtual UNIX" is unclear ..
The 'tee' command creates one for you automatically. You would use it to simultaneously look at output from a process and redirect it to a disk file (for example).
Yes you can. Unix understands both FAT32 and NTFS file systems.
You can use a piano chord identifier by playing the song on a piano or inputting the notes into the software. The identifier will analyze the notes and provide you with the corresponding chords being played in the song.