: Typically ranges from 32,000 to 128,000 tokens. A larger vocabulary reduces sequence length but increases the embedding layer's memory footprint.

: This core component allows the model to weigh the importance of different words in a sequence relative to each other. Causal Masking

: Converting raw text into a format the model can process. This involves tokenization (breaking text into smaller units like words or sub-words) and creating word embeddings (numerical vector representations).

Computers cannot read raw text. You must convert strings into numerical IDs using a vocabulary. Modern architectures typically use Byte-Pair Encoding (BPE).

Most modern LLMs (GPT series) are transformers. Your build from scratch will ignore the encoder (sorry, BERT fans). The PDF must detail how to assemble these layers:

A quality PDF on this subject isn’t just a collection of blog posts. It should be a . Here’s the table of contents you should look for: