System Monitor

System Monitor (sysmon.exe, though not to be confused with a newer Microsoft product) was a system monitoring program in Windows 95, 98 and ME that was used to monitor various activities on a computer such as CPU usage or memory usage. The much enhanced equivalent of System Monitor in the Windows NT family, perfmon.msc
or perfmon.exe
, has been variously called both System Monitor (Windows 2000, Windows XP) and Performance Monitor (Windows NT 3.x-4.0, and Windows Vista and later); its core functionality was introduced as "Performance Monitor" in Windows NT 3.1. (The Windows 9x System Monitor binary cannot run on Windows XP.) This type of application may be used to determine the cause of problems on a local or remote computer by measuring the performance of hardware, software services, and applications.