The Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of the IP address space for private internets (local networks):
10.0.0.0 – 10.255.255.255
172.16.0.0 – 172.31.255.255
192.168.0.0 – 192.168.255.255
Also, IP addresses in the range of 169.254.0.0 -169.254.255.255 are reserved for Automatic Private IP Addressing.These IP's should not be used on the Internet.
Public IP Addresses (also known as Static IP Addresses) are IP addresses that are visible to the public. Because these IP addresses are public, they allow other people to know about and access your computer, like a Web server. In some cases, you do not want people to access your computer or you want to restrict certain individuals from accessing your computer or server.