Mac does come with "Network Utility" which gives you a GUI interface for common commands such as PING, WHOIS, INFO, NETSTAT,LOOKUP,TRACEROUTE,etc. In older Macs (OS 10 - 10.8), Network Utility is found in Applications/Utilities. In the newer macs, (OS 10.9 and higher), it is found in a different location which is System/Library/CoreServices/Applications. 

However, for those that want to be adventurous, here are some terminal commands to use. 

For the following commands, en0 is usually ethernet and en1 is wireless.

To display a Mac network interface's IP address (for the wireless network interface, denoted by en1), enter this command:

ipconfig getifaddr en0

To display a Mac network interface's subnet mask, enter this command:

ipconfig getoption en1 subnet_mask

To determine the DNS server a Mac's network interface is set to leverage, enter this command:

ipconfig getoption en1 domain_name_server

To determine the DNS server a Mac's network interface is set to leverage, enter this command:

ipconfig getoption en1 domain_name_server

To determine the router and DHCP information supplied to a Mac's network interface, enter this command:

ipconfig getpacket en1