showing memory usage by process and user

Using ps on the linux terminal, we can check out memory usage - 
https://www.networkworld.com/article/3516319/showing-memory-usage-in-linux-by-process-and-user.html

"sort is being used with the -r (reverse), the -n (numeric) and the -k (key) options which are telling the command to sort the output in reverse numeric order based on the fourth column (memory usage) in the output from ps. If we first display the heading for the ps output, this is a little easier to see."

ps aux | head -1; ps aux | sort -rnk 4 | head -5