Added information about APIPA (bregman-arie#206)

* Added explanation and example of public IP address

* Removed the IP and ISP bit

* Added information about APIPA

Author: WillTheDeveloper

README.md

@@ -99,6 +99,17 @@ A set of protocols that define how two or more devices can communicate with each
 To learn more about TCP/IP, read [here](http://www.penguintutor.com/linux/basic-network-reference)
 </b></details>
 
+<details>
+<summary>What is APIPA?</summary><br><b>
+APIPA is a set of it addresses that devices are allocated
+when the main DHCP server is not reachable
+</b></details>
+
+<details>
+<summary>What ip range does APIPA use?</summary><br><b>
+APIPA uses the ip range: 169.254.0.1 - 169.254.255.254.
+</b></details>
+
 <details>
 <summary>What is Ethernet?</summary><br><b>