A Primer on Large Language Models (LLMs)

Large Language Models (LLMs) are a class of neural networks designed to understand and generate human-like text. Built on the Transformer architecture, they’re trained on massive corpora and have revolutionized natural language processing.

1. Transformer Foundations

  • Self-Attention lets the model weigh the importance of different words when encoding a sentence.
  • Multi-Head Attention captures diverse relationships in parallel.
  • Positional Encodings give the model a sense of word order.

2. Training at Scale

  • Trained on trillions of tokens (web pages, books, code).
  • Pretraining phase: predict masked or next tokens in text.
  • Fine-tuning: adapt the pretrained model to specific tasks (e.g., sentiment analysis, question answering).

3. Capabilities

  • Text Generation: drafting emails, writing code, composing poetry.
  • Completion & Summarization: finishing partial text, condensing long documents.
  • Translation & Paraphrasing.

4. Leading Models

  • GPT-4 series by OpenAI
  • LLaMA family by Meta AI
  • Claude by Anthropic
  • Gemini by Google DeepMind

5. Considerations

  • Compute & Cost: Training and inference require significant GPU resources.
  • Bias & Safety: Models can reflect biases present in training data—mitigation is an active research area.
  • Prompt Engineering: Crafting the right inputs to elicit desired outputs.

LLMs are at the forefront of AI research and productization. Upcoming posts will explore prompt design, fine-tuning workflows, and advanced use-cases like retrieval-augmented generation.