What is CPU usage?
CPU usage relates to how much processing resources are used by the computer or the amount of work that a CPU is processing. Actual CPU usage depends on the size and type of computer tasks being managed. Certain tasks require a lot of CPU time while others require fewer resources because they do not require CPU resources.
CPU usage can be used to measure system performance. For example, a heavy load with just a few programs running can indicate insufficient CPU performance or run programs that are hidden by the system monitor - a high indicator of viruses and / or malware. CPU usage should not be confused with CPU usage.