Learn the foundations,
one X at a time.
A visual, interactive companion for foundational topics that are usually explained with walls of text. Every lesson is hands-on — you click, drag, and watch the concept happen instead of just reading about it.
Subjects
Fundamental of Database
ACID, B-Trees, replication, sharding, WAL, isolation levels, and how SQL queries actually run — explained through interactive widgets you can poke at.
LIVEFundamental of Internet
How bytes get from one machine to another. IP, TCP, UDP, DNS, TLS handshakes, HTTP versions, latency — the plumbing under every URL, all interactive.
LIVEFundamental of Backend
HTTP verbs, status codes, headers, cookies, REST, request lifecycles, proxies, load balancers, caching, rate limiting — what backends actually do with the requests they receive.
Fundamental of Messaging
Brokers, topics, partitions, consumer groups, offsets, delivery semantics — the patterns behind Kafka, RabbitMQ, SQS, NATS, and everything in between.
Fundamental of Distributed Systems
Consensus (Raft), the CAP theorem, leader election, vector clocks, gossip, two-phase commit — watch nodes argue, vote, and recover from partitions in real time.
LIVEFundamental of Cryptography
Hashing, symmetric vs asymmetric, digital signatures, key exchange, certificates — animated step-by-step so you understand what's really inside a TLS handshake.
Fundamental of Design Patterns
Strategy, Observer, Factory, Decorator, DI, Repository, CQRS — vocabulary for refactoring intent. Classic GoF where it still earns its keep, plus the modern patterns the book predates.
Fundamental of Operating Systems
Processes vs threads, the scheduler, virtual memory, paging, syscalls, file descriptors — the layer beneath your code that decides whether it's fast.
Fundamental of Computer Architecture
CPU pipelines, branch prediction, cache lines, the memory hierarchy, MMU, SIMD — why two semantically identical programs run at 10× different speeds.
Fundamental of Machine Learning
Gradient descent on a loss landscape, neural networks passing activations layer by layer, k-means clusters forming in real time — the algorithms that learn from data, animated.
Fundamental of Transformers & LLMs
Tokens, embeddings, attention heads, sampling — watch how a transformer turns "Hello" into a coherent reply one matrix multiplication at a time.
Fundamental of Light
Reflection, refraction, diffraction, wavelengths, color — the physics of light through interactive optical experiments.
Fundamental of Solar Cell
How a photon becomes electricity. Bandgaps, electron-hole pairs, the P-N junction, efficiency limits — interactive physics behind every panel on every rooftop.
Fundamental of Electric Vehicles
Battery chemistry, BMS, electric motors, regenerative braking, charging curves, range estimation, and the autonomy stack — how a Tesla or BYD turns electrons into motion.
Why visual?
A picture of a B-Tree splitting is worth more than three paragraphs of prose, and an animation of a transaction rolling back beats any bullet list. This site is built for learners who want to see ideas move, not just read about them.
Each subject is a self-contained module. Today only Database is shipped — more subjects will follow.