Texts Are More than Notes, They Are Data: A Glimpse into How Machines Understand Text.

Natural language processing (NLP) has undergone extensive transformation since its infancy from rule-based systems to the sophisticated architectures of today's machine learning models. Initially, NLP relied on hard-coded grammar rules and dictionaries, which were labor-intensive and lacked flexibility. With the introduction of statistical NLP in the late 20th century, machines began learning language patterns from large datasets, improving fluency and scalability. This statistical approach evolved into machine learning models that can predict text based on context, capturing both semantic and syntactic patterns. A critical turning point was the development of word embeddings like Word2Vec (Google), which allowed machines to encode word relationships in a multidimensional space. The game-changer component, however, arrived with transformer models. Transformers address the limitations of recurrent models, enable parallel processing, and address long-range attention between words. With these models, concepts like self-attention mechanisms and positional encoding were introduced. Presently, large language models like OpenAI's GPT-5 leverage these advancements, analyzing vast amounts of text data to generate human-like text. These models embody the epitome of NLP's evolution, merging historical learnings with modern computing capabilities to deliver remarkable language understanding and generation. This report describes the inner workings of transformer models to provide radiologists with a deeper understanding of how these models work.