AI Foundations
Understand what AI is, how systems learn, where they fail, and how to judge claims without hype.
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155 plain-English guides, structured learning paths, and an open library — built by an independent 501(c)(3) nonprofit so anyone can understand modern AI.
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Each course includes explicit outcomes, mapped competencies, practice activities, and an applied capstone.
Understand what AI is, how systems learn, where they fail, and how to judge claims without hype.
Use AI productively while protecting privacy, checking outputs, and preserving human accountability.
Evaluate workplace use cases, run safe pilots, measure value, and communicate changes responsibly.
Analyze AI systems through rights, equity, governance, safety, and public-interest outcomes.
Understand language models, retrieval, agents, evaluation, cost, and deployment safeguards through practical system design.
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Direct Preference Optimization (DPO) is a way to align language models with human preferences without training a separate reward model or running…
Language AIA reward model is a neural network trained to predict how good an AI response is, acting as an automated stand-in for human judgment.
Language AIProximal Policy Optimization (PPO) is the reinforcement learning algorithm most associated with fine-tuning language models from human feedback.
Language AIBeam search is a decoding strategy that keeps the several most promising partial sequences at each step instead of greedily committing to one.
Language AINucleus (top-p) and top-k sampling are decoding methods that add controlled randomness to text generation by restricting which tokens can be chosen.
Language AIMasked language modeling teaches an AI to fill in deliberately hidden words using the full surrounding context, both left and right.
Language AINext-token prediction is the deceptively simple objective behind GPT-style models: given everything so far, guess the next chunk of text.
Language AISequence-to-sequence models map one sequence to another of possibly different length, like translating a sentence or summarizing a document.
Language AIEncoder-decoder architectures split a model into two halves: one that reads and compresses an input into a rich internal representation, and one…
Language AICross-attention is the mechanism that lets one sequence look at another: a decoder generating text can attend to an encoder's representation of the input.
Language AICatastrophic forgetting is when a neural network learns a new task and abruptly loses its ability to perform tasks it had already mastered.
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