Load, in computing, is a measure of the amount of processing a computer system is currently performing, usually in the form of a scalar and as some variation on a percentage. In a *nix variant, Server load can be calculated by the uptime, top or the w command.
[root@localhost ~]# uptime 15:33:18 up 1:33, 3 users, load average: 0.01, 0.05, 0.09
The last 3 values show the server load for 1 , 5 and 15 minutes, in that order.
This means that 1 minute back, the server load was 0.01, 5 minutes back it was 0.05 and 15 minutes back it was 0.09.