What is an IP address?
An IP address is a numerical address assigned to interfaces communicating on IP networks. It enables packets to be routed to their destination; it is not a person's name or a permanent device identity.
Address types and operation
IPv4 addresses are 32 bits long, while IPv6 addresses contain 128 bits. IPv6 provides a much larger address space. A device's private local address can differ from its public internet address. Network address translation allows a router to carry connections from several devices through one public IPv4 address. DHCP automates address assignment, while a static address remains fixed within a planned configuration. Subnet information helps determine directly reachable destinations, and the default gateway provides the starting route to other networks. One device may have multiple interfaces and addresses.
Everyday use and limitations
A phone's IP address can change when it switches from Wi-Fi to mobile data. People in one household may share a public address, so an IP alone does not establish identity or precise location. A domain name is a readable label; DNS retrieves its address records. Troubleshooting should consider the IP address, gateway and DNS together. Receiving an address does not prove that internet access works correctly. Visitor counting and security rules must account for dynamic addresses, shared networks and VPNs. For example, assuming that two visits from one IP belong to the same person, or that blocking an address affects only one user, can be wrong.