List of all users and gropus

[groups]
awk -F: '{if ($3>=500 && $3<=1000) print $1}' /etc/group
awk -F: '{if ($3>=500 && $3<=1000) print}' /etc/group | cut -d: -f1
cat /etc/group | cut -d: -f1

[users]
cat /etc/passwd | cut -d: -f1
awk -F: '{if ($3>=500 && $3<=1000) print $1}' /etc/passwd
awk -F: '{if ($3>=500 && $3<=1000) print}' /etc/passwd | cut -d: -f1
cat /etc/passwd | cut -d: -f 1,3,6 | grep "[5-9][0-9][0-9]" | grep "/home" | cut -d: -f1
cat /etc/passwd | cut -d: -f 1,3,6 | grep "[5-9][0-9][0-9]"