The difference between static and dynamic IP addresses

A static IP address is a unique address associated to a particular device or location which remains the same. This address can be altered, but requires manual intervention in order to do so. For example, a particular domain name is associated to a specific IP address. Typically the internet service provider (who will be assigning a site's IP address) will charge more for the ability to dedicate one specific IP address.

However, once a static IP is set, a site can be accessed by anyone using either the specific IP number, or, as is the case with web sites, a domain name (which is essentially a version of the IP address translated into a written name). Therefore, it is recommended that most servers are run with static IPs as it is easier for a popular location to be referenced when it is associated to just one address.

A dynamic IP address is an address that changes upon every exit and entry to the network. This is typically used when a device connects to the internet and the address is no longer associated to the device as soon as the user disconnects. When a user becomes a part of a network, in order to prevent the need to keep track of every device's IP addresses, these are assigned "on the go" and, in a sense, shared between users on a network.

There is the added benefit of security with the use of dynamic IPs, as a used IP will change after a user disconnects, however, an interrupted process (such as an upload or download) may need to be restarted if the IP has been altered.