Glossary · Internet & Web

IP Address

An IP address is a numeric label assigned to a device or server on a network, letting data packets be sent to the right destination on the internet.

Updated October 6, 2026

An IP address is a numeric identifier given to a device connected to a network that uses the Internet Protocol. It works like a postal address for packets and comes in two versions, IPv4 and IPv6.

Why it matters

Every website lives at an IP address and DNS translates domain names into it. Your own address shows up in server logs, can be used for approximate location, and may be blocked by firewalls. Many home connections get dynamic addresses that change over time.

Example

IPv4: 203.0.113.25
IPv6: 2001:db8::1

Both ranges shown are reserved for documentation. Addresses starting with 192.168. or 10. are private and only work inside a local network.

Common mistakes

  • Assuming an IP identifies a single person; many users can share one address behind NAT.
  • Hard-coding a server IP in configs, which breaks when the host changes it.
  • Blocking an IP range that also contains legitimate visitors.

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Keep reading

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