An IP address is a unique numerical label assigned to devices on a network. It tells data where to go. When you send an email, your request travels from your IP address to the server's IP address. The response comes back the same way. Without IP addresses, the internet would not know where to deliver anything.

IPv4 addresses look like 192.168.1.1. They are 32 bits long. IPv6 addresses look like 2001:0db8:85a3::8a2e:0370:7334. They are 128 bits long. Public IP addresses are visible on the internet. Private IP addresses are used inside home and office networks. NAT translates between them.

Types of IP addresses

• Public: visible on the internet
• Private: used inside local networks
• Static: does not change
• Dynamic: assigned by DHCP and can change
• IPv4 vs IPv6: old and new formats

IP addresses are not personal identifiers, but they can reveal approximate location and ISP. Websites log them. Advertisers use them. VPNs mask them by routing traffic through another server. Privacy and convenience trade off again.