Ping Utility sends requests to the specified address and lists the responses received and their round trip time. When the utility is terminated it summarizes the results, giving the average round trip time and the percent packet loss. This utility can be used to determine whether there is a problem with the network connection between two hosts.
Ping is a simple program that attempts to make a very basic kind of connection to a target machine. It provides a basic test of whether a particular host is operating properly and is reachable on the network from the testing host. It also provides estimates of the round-trip time and packet loss rate between the hosts. It works by sending ICMP packets to the target host and listening for replies. If the target machine responds ping alerts you that it is "alive", otherwise ping returns a message that the machine is unreachable. Note that the ability to ping a machine does not mean that the machine is fully functional, but it does indicate that the network path to that machine (including all routers between you and the machine) are up and functioning.
To check if a host is up and running on a network. Ping is a command that sends out a packet of data and tests to see if the other host replies back. Often used to check the integrity of a network or internetwork. Derived from the sound that a sonar system makes. A trace-route uses ping to follow the path from host to host to the intended destination.