Contribution of Dane Baker
There is a high probability for Mac power users to execute Terminal commands in order to check for network status of particular domain, such as ping, traceroute, whois, etc.
However, if we are new to Terminal commands, it is not necessary to use any web based service for this particular purpose; we can always use Network Utility pre-installed to our Mac.
Above. Running Whois with Network Utility
This application is located inside Application → Utilities folder. But I personally feel that it’s much faster to have your Spotlight do the searching task: by searching for “network utility”, you will be able to spot it (command-space to activate Spotlight).
Above. Searching for Network Utility with Spotlight