Networking
How the internet really works, and how to design networks that hold up - from your home router to the enterprise.
Watch it animated → Interactive, click-through walkthroughs for Networking concepts.Basic
How the Internet Actually Works The absolute basics of networking: what happens when you open a web page - how your request travels to a server and back, how machines find each other by address and name, and how they agree on a shared language.
IP Addresses, DNS & Ports, Explained The address book of the internet: what an IP address really is, how DNS turns names like example.com into numbers, and how ports let one machine run many services at once.
HTTP, Explained - the language the web speaks What HTTP actually is: every time you load a page, your browser sends a request and a server sends a response. This guide makes that conversation - methods, status codes, headers, cookies, and the S in HTTPS - finally make sense.
Your Home Network, Explained What that box on your shelf actually is - the modem connects you to your ISP, the router shares that connection with all your devices, NAT lets them share one public IP, and a few settings keep the whole thing safe.
What a VPN Actually Does What a VPN really routes and hides, and what it does not: the encrypted-tunnel model, who can see what, and when a VPN is mostly theater.
Intermediate
The TCP/IP Model Without the Acronym Soup The layered model, finally intuitive: each layer does one job and trusts the layer below, like nesting envelopes - Link, Internet, Transport, Application, plus TCP vs UDP and a packet's round trip.
Troubleshooting Networks A calm, methodical way to debug 'the internet is broken' - work up the layers (link, IP, gateway, DNS, destination), then use ping, traceroute, dig, and a packet capture to read exactly where the conversation died.
Email, Demystified (SPF, DKIM, DMARC) How email really travels and why yours lands in spam: SMTP, plus the three DNS records that prove a message is truly from your domain.
Advanced
Designing an Enterprise Network How to grow from a single home router into a network that holds up: segmentation to limit blast radius, scaling and redundancy to survive load and failure, and a security edge - firewalls, DMZ, VPN, zero-trust - that keeps the inside safe.