Understand how IP addresses work, the differences between public and private addressing, and how IPv4 and IPv6 compare.
Master IP address formats: dotted decimal, binary, hexadecimal, and integer. Learn to convert between them by hand, identify IP classes, and see why format parsing ambiguity has caused real security bugs.
Understand the IPv4 vs IPv6 differences with a 2026 perspective. Learn why IPv4 ran out, how IPv6 solves it, and what the March 2026 majority milestone on Google means for your network.
Understand public vs private IP addresses, how NAT bridges them, and the often-missed fourth range (RFC 6598’s 100.64.0.0/10) that ISPs now use for carrier-grade NAT on mobile and satellite networks.
TL;DR — Key Takeaways Your public IP address is the address the rest of the internet sees when your devices connect. It is assigned by your ISP, not by you. The fastest way to find it is to use a web-based IP lookup tool. One click. You can also check your IP from the command … Read more