De acordo com TechNet :
The number of input/output operations generated by a process that are neither reads nor writes, including file, network, and device I/Os. An example of this type of operation would be a control function. I/O Others directed to CONSOLE (console input object) handles are not counted.
Se você precisar de informações mais detalhadas do que o Gerenciador de Tarefas, dê uma olhada no Process Explorer e no Process Monitor da Sysinternals.