Learn networking and Linux the visual way.
Animated, step-by-step lessons that show — not just tell. Built for IT students, sysadmins, and the just-curious. Pace it yourself; nothing autoplays.
Animated interactive lessons for Linux and networking — TCP/IP, DNS, TLS, HTTP, chmod, process lifecycle, SSH key authentication, and more.What happens when you type a URL?
The most-asked tech interview question, animated end to end. Five chapters take you from keystroke to pixels: DNS resolution, TCP handshake, TLS handshake, HTTP exchange, and browser render. Step through at your own pace.
- 01DNS resolution
- 02TCP 3-way handshake
- 03TLS handshake
- 04HTTP request/response
- 05Browser render
tracks · structured study paths
Red Hat certification track
The full RHCSA (EX200) and RHCE (EX294) syllabus, organized by Red Hat's official course breakdown. RHEL-specific deep dive.
Linux+ certification track
The four exam domains of CompTIA's vendor-neutral Linux certification mapped to our lessons and tools. Distro-agnostic.
networking · 4 lessons
What happens when you type a URL?
The most-asked interview question, animated. Five chapters: DNS → TCP → TLS → HTTP → Render. Step through each at your own pace.
OSI / TCP-IP layers
A packet wrapped layer-by-layer, then unwrapped on the other side. Watch headers stack and peel off.
DNS deep dive
Beyond the basics: recursive vs iterative, cache layers, TTLs, glue records, and what `dig +trace` actually shows.
NAT and routing
How packets cross networks. Source NAT, destination NAT, routing tables — visualized with real IPs.
linux · 8 lessons
SELinux contexts
Why Apache can't read your file. Watch the policy engine decide — and learn the workflow for fixing denials. RHCSA-ready.
Linux boot process
From power button to login prompt. Every stage in the chain — UEFI, GRUB, kernel, initramfs, systemd — with the rescue moves that save you. RHCSA-ready.
LVM stacking
Layer-by-layer build of an LVM stack: disks → PVs → VG → LVs → filesystem. Then extend live and snapshot. RHCSA-ready.
systemd targets
How systemd organizes services with dependencies and targets. Visual dependency graph, target nesting, and the isolate trick. RHCSA-ready.
Command line essentials
Six animated chapters take you from 'what's that $ symbol?' to chaining commands with pipes. Live terminal transcripts as you step through. On-ramp for everything else.
File system hierarchy
Animated tour of every important top-level directory on Linux. /etc, /var, /usr, /home, /tmp, /proc, /dev — what they're for and what lives there.
chmod, visualized
Click bits, watch them flip. See `rwx` ↔ `755` ↔ binary in lockstep. Includes setuid, sticky, and group inheritance.
Linux process lifecycle
fork, exec, wait, exit — animated. See how every program on Linux is born, runs, and dies.
security · 2 lessons
How SSH key auth works
The challenge–response dance between client and server, without ever sending the private key. Animated.
TLS handshake, deep
Beyond the simplification: cipher suites, key derivation, perfect forward secrecy, SNI, ALPN. Animated.
Cards marked SOON are designed and on the roadmap — they don't exist yet. New lessons drop as their animations are ready.