network object group is a group of any of the following objects:
â¢Hostnames
â¢Host IP addresses
â¢Subnets
â¢Ranges of IP addresses
â¢Other network object groups
service object group is a group of any of the following objects:
â¢Source and destination protocol ports (such as Telnet or Simple Network Management Protocol (SNMP))
â¢ICMP types (such as echo, echo-reply, or host-unreachable)
â¢Top-level protocols (such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), or Encapsulating Security Payload (ESP))
â¢Other service object groups
http://www.cisco.com/en/US/docs/ios/security/configuration/guide/sec_object_group_acl.html#wp1092177