The only referenced material in the man page is w(1) which tells this:
The load average numbers give the number of jobs in the run queue
averaged over 1, 5 and 15 minutes.
What are those "jobs"? I guess they are not processes. What is that
"run queue"? Which is better, the lower or the higher number?
A job is a runnable process. The run queue is a list containing the
processes which are runnable at a particular time. Lower numbers
indicate lower CPU load. From "man getloadavg":
The getloadavg() function returns the number of processes in
run queue averaged over various periods of time. Up to nelem
retrieved and assigned to successive elements of loadavg.
imposes a maximum of 3 samples, representing averages over the
last 1, 5,
and 15 minutes, respectively.