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Artificial IntelligenceTopic Knowledge Hub

Computing & Artificial Intelligence

From foundational machine learning to modern generative architectures: self-attention, token sampling, and autonomous agent loops.

12 Published Explainers
49 Systems Analyzed
89 Core Concepts
3 Inquiry Path
Recommended Starting Point

How AI Agents Work

The architectural loop behind autonomous planning, tool execution, and stateful problem solving

Core Question Answered
“What actually happens behind the scenes when an AI agent solves a problem on its own?”
Agent RuntimeReAct PatternFunction CallingWorking Memory Context
Read Explainer

Inquiry Learning Paths

Structured sequences designed to take you from a familiar question to complete first-principles understanding.

All Learning Paths
Computing & Silicon Architecture · 8 Core Steps

How Computers Execute and Store Information

Progress from quantum band gaps in doped silicon to CMOS logic gates, binary adders, pipelined CPU instruction execution, coherent SRAM caches, and operating system kernels.

Full Path Map
Starting Question

“How does purified quartz sand doped with boron and phosphorus become a microprocessor capable of executing billions of arithmetic instructions and running an operating system every second?”

Prerequisites:Positional Place-Value Notation & Base-2 Binary NumbersElectrical Voltage Thresholds & Capacitive Charge StoragePiezoelectric Quartz Harmonic Oscillation
1

How Semiconductors and Transistors Actually Work

Explains how doping silicon crystals creates p-n junctions and voltage-controlled MOSFET switches with zero moving parts.

2

How Binary and Logic Gates Became Computation

Shows how Claude Shannon mapped George Boole’s symbolic logic onto physical on/off switches (AND, OR, NOT, XOR) to represent numbers and decisions.

3

How CMOS Transistors Form Logic Gates

Details how complementary PMOS pull-up and NMOS pull-down transistor networks implement logic gates with near-zero static power dissipation.

4

How Binary Arithmetic Logic Units Actually Add Numbers

Combines XOR and AND gates into half-adders, full-adders, and carry-lookahead circuits that perform binary addition, subtraction, and comparisons in picoseconds.

5

How a CPU Executes an Instruction

Steps through the Fetch–Decode–Execute–Writeback pipeline, register files, branch prediction, and out-of-order execution inside a modern processor core.

6

How CPU Cache Hierarchies Overcome the Memory Wall

Explains why main DRAM is hundreds of times slower than the ALU—and how L1/L2/L3 SRAM caches and MESI coherence protocols prevent processor stalls.

7

How an Operating System Actually Runs Software

Reaches the software abstraction layer: how the OS kernel uses hardware timer interrupts, virtual-memory page tables, and system calls to multiplex applications safely.

8

How Compilers Translate Human Code into Machine Instructions

Completes the journey from human thought to silicon execution: how compilers lex, parse, optimize via SSA form, and allocate hardware registers to emit native machine code.

Endpoint:You understand the entire computing stack without black boxes: how electric fields in doped silicon form CMOS logic gates, how gates compose into a clocked ALU and pipelined CPU with coherent SRAM caches, and how an operating system kernel schedules virtual-memory processes on top of that hardware.
Networks & Telecommunications · 7 Core Steps

How the Internet Carries Information Around the World

Follow a network request across every physical and protocol layer: BGP autonomous systems, IP packet hops, submarine optical amplifiers, 802.11 Wi-Fi radio modulation, Anycast DNS, and TLS cryptography.

Full Path Map
Starting Question

“When you tap a link or type a web address on your phone, how do your request packets travel through air as radio waves and across ocean floors as laser pulses to fetch a webpage in milliseconds?”

Prerequisites:Binary Bitstreams & Packet Header EncapsulationElectromagnetic Spectrum (Microwave Radio vs. 1550 nm Infrared Light)Modular Arithmetic & One-Way Trapdoor Functions
1

How the Internet Actually Works

Introduces the global network of networks: 115,000+ independent Autonomous Systems exchanging reachability paths via BGP-4 and forwarding 1,500-byte packets without central control.

2

How Packets Actually Travel Across the Internet

Follows an individual packet hop-by-hop: TCP segmentation, IPv4/IPv6 TTL decrementing, longest-prefix-match TCAM lookups, and dynamic rerouting around severed links.

3

How Fiber-Optic Cables Carry Light Across Oceans

Descends to the ocean floor where 99% of intercontinental traffic travels as 1550 nm infrared laser light through silica fibers amplified every 70 km by erbium-doped optical repeaters (EDFAs).

4

How Wi-Fi Actually Works

Explains the wireless last hop: how your router maps digital bits onto 2.4/5/6 GHz QAM radio subcarriers (OFDMA) and coordinates airtime via CSMA/CA collision avoidance.

5

How Cellular Networks Route Calls and Data

Extends wireless routing to mobile wide-area telecommunications: microsecond base station MAC scheduling, RRC connection handshakes, seamless inter-tower handovers, and GTP tunnels across LTE and 5G cores.

6

What Happens When You Type a Website Address

Connects packet transport to the application layer: hierarchical Anycast DNS resolution, the TCP three-way handshake, TLS 1.3 key exchange, and browser DOM rendering.

7

How Public-Key Cryptography Actually Works

Explains the mathematical miracle behind HTTPS and TLS: how two computers that have never met establish an encrypted channel over public fiber using Diffie-Hellman and elliptic-curve cryptography.

Endpoint:You can trace a web request across every physical and protocol layer—from a capacitive finger tap and 802.11 QAM radio waves, through Anycast DNS, BGP autonomous systems, and erbium-doped submarine fiber-optic repeaters, to a TLS 1.3 elliptic-curve handshake.
Artificial Intelligence & Autonomous Systems · 4 Core Steps

How AI Systems Reason and Act in the Real World

Trace modern artificial intelligence from transformer self-attention and next-token probability distributions to autonomous agent loops and structured tool execution.

Full Path Map
Starting Question

“How does a neural network trained only to predict the next token become an autonomous software agent capable of invoking external APIs, querying databases, and executing multi-step plans?”

Prerequisites:High-Dimensional Vector Embeddings & Matrix Dot ProductsConditional Probability Distributions & Softmax Logit SamplingStructured JSON Schemas & Deterministic Runtime Sandboxes
1

How Large Language Models Generate Text

Establishes the cognitive engine: subword BPE tokenization, high-dimensional vector embeddings, multi-head self-attention (Q, K, V matrices), and autoregressive next-token probability sampling.

2

How Transformers Changed AI

Explains the architectural revolution that solved sequential recurrence, detailing scaled dot-product attention mathematics, multi-head representation subspaces, and empirical neural scaling laws.

3

How AI Agents Work

Wraps the stateless language model inside an iterative runtime harness—introducing the Observe–Think–Act–Reflect control loop, working context windows, and persistent episodic memory.

4

How an AI Agent Decides Which Tool to Use

Shows how probabilistic token generation bridges to deterministic software execution via JSON schema constrained decoding, semantic tool routing, and host runtime validation.

Endpoint:You can trace an AI system from matrix dot products and softmax token probabilities inside a transformer, through the iterative Observe–Think–Act–Reflect runtime loop, to constrained JSON tool calls verified by a host sandbox.

All Published Explainers

Every verified first-principles analysis in this domain.

Explainer

How AI Agents Work

The architectural loop behind autonomous planning, tool execution, and stateful problem solving

First-Principles ExplainerRead
Explainer

How Large Language Models Generate Text

From raw prompt strings to token embeddings, self-attention calculations, and next-token probability sampling

First-Principles ExplainerRead
Explainer

How Search Engines Actually Work

How search engines crawl the web, build inverted indexes, and rank billions of pages in 150 milliseconds using BM25, PageRank, and neural vector search

First-Principles ExplainerRead
Explainer

How an AI Agent Decides Which Tool to Use

The mechanics of schema matching, token probabilities, and semantic tool routing

First-Principles ExplainerRead
Explainer

Why AI Chatbots Sometimes Make Things Up

The mechanics of hallucination, probability vs. truth, and the engineering behind grounded AI responses

First-Principles ExplainerRead
Explainer

Why Search Results Differ Between People

Geographic IP Anycast routing, session history vectors, freshness ranking, and A/B experiment flight allocation

First-Principles ExplainerRead
Explainer

Why Neural Networks Were Invented

From McCulloch-Pitts threshold logic and the Rosenblatt perceptron to Minsky's XOR crisis and the backpropagation revolution

First-Principles ExplainerRead
Explainer

How Transformers Changed AI

From sequential recurrence and vanishing gradients to scaled dot-product attention, multi-head projections, and modern neural scaling laws

First-Principles ExplainerRead
Explainer

How Reinforcement Learning from Human Feedback (RLHF) Aligns AI

From Bradley-Terry preference modeling and PPO reward hacking to KL divergence penalties and direct preference optimization

First-Principles ExplainerRead
Explainer

How Mixture of Experts (MoE) Scales Large Language Models

From dense transformer bottlenecks and sparse gating to top-k routing, expert capacity, and Mixtral parameter scaling

First-Principles ExplainerRead
Explainer

How Vector Search and Dense Retrieval Work

From word embeddings and bi-encoder transformers to cosine similarity, HNSW small-world graphs, and product quantization

First-Principles ExplainerRead
Explainer

How AI Agent Memory Systems Work: From Working Context to Episodic Recall

From context window limits and virtual memory paging to vector recall, recursive summarization, and self-reflective memory consolidation

First-Principles ExplainerRead

Technical Systems & Protocols Analyzed

Hardware, protocol switches, and central clearing houses examined in this hub.

Large Language ModelSandbox EnvironmentTool API GatewayTransformer Neural NetworkTokenizer BPE EngineInference Server (KV Cache)Distributed Web Crawlers (Googlebot)Inverted Index ShardsDocument Forward IndexLink Graph EngineServing Cache & Query AggregatorCross-Encoder Neural Re-rankerFunction RegistrySemantic RouterVector DatabaseRAG PipelineRLHF Reward ModelGeolocation Edge ResolverShort-Term Session Memory StoreReal-Time Freshness Ingestion StreamExperimentation & Traffic Splitting FrameworkMobile-First Rendering PipelineThreshold Logic Unit (TLU)Mark I Perceptron Optical HardwareMultilayer Feedforward Artificial Neural NetworkGradient Descent Optimization RuntimeTransformer Encoder-Decoder ArchitectureDecoder-Only Generative Pre-trained Transformer (GPT)GPU Tensor Core Matrix Multiplier PipelineKey-Value (KV) Inference CacheLarge Language Model (LLM)Reward Model (RM)Reference Policy (SFT Frozen Model)Actor-Critic ArchitecturePPO Training LoopTransformer MoE Layer ArchitectureLinear Router Gating NetworkDistributed All-to-All Collective Communication BusParallel SwiGLU Feed-Forward Expert BlocksHardware Memory Bandwidth vs Compute Saturation PipelineTransformer Text Encoder (BERT / ModernBERT / ColBERT)High-Dimensional Vector Embedding SpaceHNSW Multi-Layer Skip-Graph IndexProduct Quantization Sub-Vector CodebookHybrid Retrieval & Cross-Encoder Re-Ranker PipelineLLM Context Window (Active Working Memory)Vector Database Long-Term Store (Pinecone, Qdrant, Chroma)External Relational / Graph State Engine (PostgreSQL, Neo4j)Background Memory Consolidation & Maintenance Workers
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