How TCP Works
Connection setup, sequence numbers, acknowledgements, retransmission, and flow control.
Read guideHow Things Work
Plain-English guides for networking, web infrastructure, and AI concepts
These pages are written for developers who need the practical version of a concept before going deeper into specs, papers, or framework internals. The goal is to explain the moving parts clearly enough that logs, dashboards, and code make more sense.
The collection spans network transport, encryption, request handling, data systems, and modern machine learning building blocks. Each guide focuses on the core mechanism, the important vocabulary, and the mistakes people commonly make when talking about the topic.
Networking and web guides
Start here if you want a better mental model for how requests move across the internet and what sits between a browser and an application server.
How SSL and TLS Work
Certificates, handshakes, session keys, and why SSL is mostly a legacy name now.
Read guideHow DNS Works
How names become IP addresses, where caches live, and why propagation is never truly instant.
Read guideHow HTTP Works
Methods, headers, status codes, request-response behavior, and statelessness.
Read guideHow REST APIs Work
Resources, verbs, idempotency, payloads, and the practical shape of a typical API.
Read guideHow WebSockets Work
Upgrades, persistent connections, and when a duplex channel is better than polling.
Read guideDiagram-led explainers
Each page now opens with a colorful original diagram so readers can build the mental model quickly before reading the detailed sections.
How these guides are written
These pages are meant to be read by working developers, not only students. Each guide tries to answer three questions quickly: what the system is for, what the core mechanism is, and what people commonly misunderstand when debugging or discussing it.
The format is intentionally repetitive because repetition helps readers scan: a plain-language introduction, an original diagram when useful, a breakdown of the moving parts, and a short list of common confusions. The aim is to make the page useful even if someone reads only one section while triaging an issue.
Suggested reading paths
If you are following a request from the browser to the backend, or moving from classic web infrastructure into AI application behavior, these sequences are a better starting point than random article hopping.
From name lookup to server response
Start with DNS, then TCP, TLS, HTTP, REST APIs, and WebSockets to understand how clients locate, connect to, and talk with services.
Start with DNSWhat happens after the request arrives
Continue with databases and CDNs to understand storage, caching, latency reduction, and the tradeoffs between freshness and speed.
Read databasesFrom classic models to chat products
Use CNN, RNN, transformer, and ChatGPT guides together if you want a compact ladder from model families to deployed conversational systems.
Start with CNNsWhat these guides are and are not
They are original summaries designed to improve working intuition. They are not standards documents, legal security guidance, or exhaustive research surveys. If you need implementation details for production systems, the best next step after these pages is still the relevant RFC, vendor documentation, or research paper.
That boundary matters because the point of this guide library is to reduce confusion, not create false confidence. The ideal outcome is that a reader leaves with clearer vocabulary, a more accurate mental model, and a better sense of what to read next.
Systems and data guides
These explainers focus on the infrastructure layers that shape latency, consistency, and scale in real applications.
How Databases Work
Storage engines, indexes, transactions, and why reads and writes behave differently.
Read guideHow CDNs Work
Edge caches, cache keys, invalidation, and how content gets closer to users.
Read guideMachine learning and AI guides
These pages strip the topic down to the important mechanism so the common terms around deep learning are easier to decode.
How CNNs Work
Convolutions, filters, feature maps, pooling, and why CNNs were strong at image tasks.
Read guideHow RNNs Work
Hidden state, recurrence, sequence processing, and why long context is hard for them.
Read guideHow Transformers Work
Tokens, embeddings, self-attention, layers, and next-token prediction.
Read guideHow ChatGPT Works
How a chat product is built on top of a large language model and inference pipeline.
Read guideAll explainer pages
How TCP WorksReliable ordered delivery over an unreliable network.
How SSL and TLS WorkCertificates, encryption, and secure session setup.
How DNS WorksName resolution, recursive resolvers, and caching.
How HTTP WorksRequest-response basics for browsers and APIs.
How REST APIs WorkResource-oriented API design and behavior.
How WebSockets WorkPersistent bidirectional communication over one connection.
How Databases WorkStorage, indexing, querying, and transactions.
How CDNs WorkEdge delivery and caching across geographic regions.
How CNNs WorkConvolutional neural networks for spatial pattern detection.
How RNNs WorkRecurrent neural networks for sequential data.
How Transformers WorkSelf-attention and scalable sequence modeling.
How ChatGPT WorksChat interfaces, large language models, and generated responses.