Dynamic IP vs Static IP
Static IP addressing is for one customer on one IP address and Dynamic IP addressing assigns a different IP address each time the ISP customer logs on to their computer, but this is dependent upon the Internet Service Provider (ISP) because some ISP's only change the IP address as they deem it necessary.
If you have Dynamic IP Addressing through your Website Host it means that you are sharing an IP Address with several other customers.
If you are a beginner on the internet, an avid internet user, are entertaining the thought of starting your own website business, are a gamer, use VOIP or VPN there are several things you should know about IP Addressing.
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In contrast, Dynamic IP addressing should not be used for VOIP, VPN, playing online games or game hosting because Dynamic IP addressing is less reliable then Static IP addressing and could cause the service to disconnect while you are on a VOIP, VPN or gaming.
Source
http://whatismyipaddress.com/dynamic-static