If we feel the system might be slow, we can check the system load by using the uptime command. It outputs the first line output by the w command:
$uptime 1:57pm up 38 min, 1 user, load average: 0.00, 0.06, 0.06 $
This tells us the current system time, the time the system has been running, the number of users using the system and the load average over the last 5, 10 and 15 minutes. Depending on the system we are using a load of 1 might be high, on other systems however a load of 10 might be high. The load average just represents relative values.