Process identifier, or more commonly know as PID or process ID, is a unique number tagged with each processes running on a system, and used by some operating system kernels, such as UNIX, Linux, Mac OS X and Windows) to identify a process.

In Unix-like and Linux operating system, ps command can be used to search for the PID for a particular running process, by grepping the output. In Windows operating system such as Windows XP, Windows Vista, Windows Server 2003, Windows Server 2008 and Windows 7, there is no such utility or command available though.

In order to get to know, or view, retrieve and identify the process ID or PID of the processes running in Windows operating system, users or administrators can make use of Task Manager. However, Task Manager does not display PID information by default. To display the PID value in Task Manager, go to Processes tab, click on View menu, then click on Select Columns…. In the “Select Columns” or “Select Process Page Columns” dialog, tick and check the checkbox for PID (Process Identifier), and click OK.

Enable and Turn On PID on Windows Task Manager

To run Task Manager, use Taskmgr command or right click on Taskbar, and select “Task Manager”.