Resource monitor is a application which comes with windows which many of us are not aware about you can use it to monitor CPU, Disk, memory and network processes. You can open it by going to start, all programs, accessories, resource monitor or by typing resmon.exe in run

Overview tab
The overview tab shows details about CPU, Disk, Memory, network it shows the main detailsOn the right side the computer automatically generates graphs for the CPU, memory, network, disk usage