Foundation Models Explained: Transformers, Scaling Laws & RLHF | Chapter 2

onepagecode · Advanced ·🧠 Large Language Models ·4w ago

About this lesson

Download the source code from here: https://onepagecode.substack.com/ In this chapter, we go deep into how foundation models actually work — from the famous Transformer architecture to why bigger models need more data (Scaling Laws), and how post-training (SFT + RLHF) makes models usable. This is one of the most important chapters if you want to truly understand modern AI systems like GPT, Claude, Llama, and Gemini. What you’ll learn in this video: • Why training data quality and distribution matter so much • Multilingual and domain-specific models • The Transformer architecture and the Attention mechanism (explained simply) • Model size, parameters, and the Chinchilla Scaling Law • Pre-training vs Post-training (Supervised Finetuning + Preference Tuning) • RLHF and Reward Models explained • Sampling strategies: Temperature, Top-k, Top-p • Why LLMs hallucinate and behave inconsistently • Structured outputs and test-time compute This chapter builds the technical foundation needed to understand model selection, evaluation, and adaptation in later chapters. If you're preparing for AI engineering interviews, building LLM applications, or just want a clear technical understanding of how these models work under the hood, this video is for you. Drop a comment: Which part of foundation models confuses you the most — Attention, Scaling Laws, RLHF, or Hallucinations? #FoundationModels #TransformerArchitecture #LLM #ScalingLaws #RLHF

Original Description

Download the source code from here: https://onepagecode.substack.com/ In this chapter, we go deep into how foundation models actually work — from the famous Transformer architecture to why bigger models need more data (Scaling Laws), and how post-training (SFT + RLHF) makes models usable. This is one of the most important chapters if you want to truly understand modern AI systems like GPT, Claude, Llama, and Gemini. What you’ll learn in this video: • Why training data quality and distribution matter so much • Multilingual and domain-specific models • The Transformer architecture and the Attention mechanism (explained simply) • Model size, parameters, and the Chinchilla Scaling Law • Pre-training vs Post-training (Supervised Finetuning + Preference Tuning) • RLHF and Reward Models explained • Sampling strategies: Temperature, Top-k, Top-p • Why LLMs hallucinate and behave inconsistently • Structured outputs and test-time compute This chapter builds the technical foundation needed to understand model selection, evaluation, and adaptation in later chapters. If you're preparing for AI engineering interviews, building LLM applications, or just want a clear technical understanding of how these models work under the hood, this video is for you. Drop a comment: Which part of foundation models confuses you the most — Attention, Scaling Laws, RLHF, or Hallucinations? #FoundationModels #TransformerArchitecture #LLM #ScalingLaws #RLHF
Watch on YouTube ↗ (saves to browser)
Sign in to unlock AI tutor explanation · ⚡30

Related Reads

📰
I compared the real cost of running LLMs on AWS - here's when each option makes sense
Learn when to use each AWS option for running LLMs in production and understand their cost implications
Dev.to · Jerzy Kopaczewski
📰
Building a Character-Level Bigram Language Model from Scratch with PyTorch
Learn to build a basic character-level bigram language model from scratch using PyTorch, understanding the fundamentals of neural language modeling
Dev.to · Mohamed Heni
📰
Running NVIDIA Nemotron 3.5 ASR Locally with parakeet.cpp (and how it beat Whisper on my laptop)
Run NVIDIA Nemotron 3.5 ASR locally for offline speech-to-text capabilities without relying on cloud services or incurring API bills
Medium · LLM
📰
When Does a Prompt Become an Undocumented Program?
Learn to identify when a prompt becomes an undocumented program and why it matters for effective AI integration in analyst work
Dev.to · Yura Solovey
Up next
5 Levels of AI Agents - From Simple LLM Calls to Multi-Agent Systems
Dave Ebbelaar (LLM Eng)
Watch →