ps gu|head -n 1;ps gau|egrep -v "CPU|kproc"|grep "${user}"|grep
-v grep|sort +2b -3 -n -r|head -n 10;uptime

first set
ps -gu -- gives a display of all processes by group name in a user readble format
head -n 1 --prints the the first line of output piped to it from the first command.
The output of this command is probably (I didnt
run it) just the headings of the ps command.

second set
ps -gau - selection of all processes, in a readable format
egrep -v "CPU|kproc"|grep "${user}"|grep
-v grep|- a search string, basically it ignores and does not output
any lines that have "CPU" or "kproc" in them and outputs all lines
with the value of ${user}. It also ignores any grep string.

sort +2b -3 -n -r|head -n 10 - numeric sort of teh 2nd and third
fields, ignoring blank space and in reverse order.
uptime - prints a display of how long the system has been running