01
AI Foundations
Understand what AI is, how systems learn, where they fail, and how to judge claims without hype.
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117 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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Five outcome-based courses
Each course includes explicit outcomes, mapped competencies, practice activities, and an applied capstone.
02
Responsible AI User
Use AI productively while protecting privacy, checking outputs, and preserving human accountability.
03
AI at Work
Evaluate workplace use cases, run safe pilots, measure value, and communicate changes responsibly.
04
AI Policy & Society
Analyze AI systems through rights, equity, governance, safety, and public-interest outcomes.
05
Building with AI Systems
Understand language models, retrieval, agents, evaluation, cost, and deployment safeguards through practical system design.
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FundamentalsCore concepts: how AI works at a high level.84 guides Language AILLMs, NLP, ChatGPT, prompting, and text understanding.155 guides Visual AIImage generation, computer vision, video, and design.133 guides Audio AIVoice, music, podcasting, and audio-first AI.117 guides CompaniesProfiles of OpenAI, Anthropic, Google, Meta, and more.121 guides ApplicationsHow AI shows up in coding, search, agents, and daily life.111 guides IndustriesAI in healthcare, finance, education, energy, and more.91 guides TechnicalChips, fine-tuning, RAG, vectors, and AI infrastructure.177 guides SocietyBias, privacy, copyright, safety, and the AI future.30 guides
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Audio AI
Spleeter Stem Separation
Spleeter is an open-source tool from Deezer that splits a finished song into separate tracks (vocals, drums, bass, and more) using deep learning.
Audio AICREPE Pitch Estimation
CREPE is a deep-learning model that estimates the fundamental frequency (pitch) of a monophonic audio signal directly from its raw waveform.
Audio AIPESQ and STOI Speech Quality Metrics
PESQ and STOI are standard objective metrics that score how good processed speech sounds and how understandable it is, without needing human listeners.
Audio AISource-Filter Vocoding and WORLD
A vocoder is a tool that takes speech apart into its building blocks and rebuilds it.
Audio AIMean Opinion Score Evaluation
Mean Opinion Score (MOS) is a 1-to-5 average rating from human listeners that measures how good synthesized or transmitted audio sounds.
Audio AIConstant-Q Transform for Audio
The Constant-Q Transform (CQT) is a frequency analysis that uses logarithmically spaced bins matched to musical pitch, instead of the evenly spaced bins…
Audio AIFilterbank and PLP Features
Filterbank and Perceptual Linear Prediction (PLP) features are ways of summarizing a speech signal into compact, perceptually meaningful numbers that machine…
Audio AIStyleTTS 2 Style Diffusion
StyleTTS 2 is a text-to-speech model that treats voice 'style' — prosody, emotion, and speaker timbre — as a random variable sampled with a diffusion model…
Audio AIFastPitch Pitch-Controllable TTS
FastPitch is a fast, non-autoregressive text-to-speech model that explicitly predicts the pitch (fundamental frequency) of every input token, letting you…
Audio AIVoicebox Flow-Matching Speech Generation
Voicebox is Meta's text-guided speech generation model trained with a flow-matching objective to 'fill in' masked audio, letting one model do zero-shot voice…
Audio AIDeep Noise Suppression Challenge
The Deep Noise Suppression (DNS) Challenge is a Microsoft-run competition that pushes researchers to build neural networks that strip background noise…
Audio AISpectral Subtraction and Wiener Filtering
Spectral subtraction and Wiener filtering are the classic, pre-deep-learning workhorses of noise reduction.
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