See system users list:
/user print
You can't see passwords...
[admin@MikroTik] > user export
# oct/02/2007 08:33:25 by RouterOS 2.9.27
#
/ user
add name="admin" group=full address=0.0.0.0/0 comment="system default user" disabled=no
/ user group
add name="read" policy=local,telnet,ssh,reboot,read,test,winbox,password,web,!ftp,!write,!policy
add name="write" policy=local,telnet,ssh,reboot,read,write,test,winbox,password,web,!ftp,!policy
add name="full" policy=local,telnet,ssh,ftp,reboot,read,write,policy,test,winbox,password,web
/ user aaa
set use-radius=no accounting=yes interim-update=0s default-group=read
[admin@MikroTik] >