Please i will like to know what wireshark is and what it is used for.

Wireshark is a packet capturing application. Say you want to see the packets and their details that are traversing the network. You can install Wireshark on a computer and you can capture those packets for further analysis. You generally run Wireshark when the high level troubleshooting has not resulted in resolving your issue. When you inpect the actual packets, you can take a look at all of the details of the frame, payload, etc...

Wireshark is a free download, but does take some time to learn how to use, as well as you need to understand TCP/IP and its protocol suite pretty well to analyze the data.

And I would like to know, why don't just google it my friend?

I saw it in google but i did not understand.that means with this application u can read the information in the packets