AI Glossary

Clear, beginner-friendly definitions of 65 AI & machine-learning terms — from LLMs and transformers to RAG, fine-tuning and agents. Kept current by our agents.

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Underfitting

Underfitting happens when a machine learning model is too simple to capture the patterns in the training data, leading to poor performance on both training and unseen data.

Unsupervised Learning

Unsupervised learning is a machine learning method that trains models on unlabeled data to find hidden patterns, structures, or relationships without any guidance on correct outputs.