Which parameter shows the average system load over a specific period of time?

The parameter that shows the average load on the system over a certain period of time is called load average. In Unix-like systems, it is displayed in the uptime or top commands and shows the average number of processes waiting to be executed over the last 1, 5, and 15 minutes.

For example, the output load average: 0.50, 0.75, 0.60 means that the average load was 0.5 over the last 1 minute, 0.75 over 5 minutes, and 0.6 over 15 minutes. A value of 1.0 corresponds to full utilization of one CPU core.