Generally, there can be two types of IP addresses – static and dynamic. Static is an unchanging IP address, but most computers use dynamic IP addresses for better connectivity. A DHCP server assigns the dynamic IP address.

Static is a fixed IP address. However, most workstations practice dynamic IP numbers. Hence at present, there are not sufficient static IP details in the IT world to manage all the requests. Hence, there was a requirement to deliver PCs the capability to share IP addresses.

For more info:  DHCP Role
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