Fundamentals

13 topics in AI & Machine Learning

AI Hallucinations

ChatGPT sometimes makes up facts with total confidence. Here's the weird reason why — and why it's not as simple as 'the AI lied.'

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Artificial Intelligence

What is AI really? Think of it as a dog that learned tricks — impressive, but it doesn't know why it's doing them.

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Bias-Variance Tradeoff

The fundamental tension in machine learning between being wrong in the same way vs. being wrong in different ways — and why the simplest model isn't always best.

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Deep Learning

Why your phone can spot your face in a messy photo album — and why that trick comes from practice, not magic.

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Embeddings

How do computers know that 'dog' and 'puppy' mean almost the same thing? They don't read definitions — they turn words into secret map coordinates, and nearby coordinates mean nearby meanings.

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Generative AI

Generative AI doesn't look things up — it makes things up. Here's why that's either impressive or terrifying, depending on what you ask it to make.

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Gradient Descent

How AI finds the right answer the same way a blindfolded hiker finds their way downhill — by feeling which direction the ground slopes.

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Large Language Models

ChatGPT doesn't 'know' anything — it learned to complete sentences so well it looks like thinking. Here's the weird trick that makes it work.

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Machine Learning

Machine learning isn't magic — it's a piano student who practices millions of songs until the music just flows. Here's what that actually means.

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Model Evaluation

How we know if an AI model is actually good — the metrics and testing methods that separate genuinely useful AI from AI that only looks impressive.

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Neural Networks

Your brain is made of billions of tiny switches that fire together to recognize your mom's face. Neural networks steal that same trick — and use it to beat you at chess.

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Tokenization — Explain It Like I'm 5

Why does ChatGPT charge by 'tokens' and not words? The weird way AI reads text — and why it matters more than you think.

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Transformer Architecture

Every AI you've talked to in the last 5 years runs on the same weird trick — paying 'attention' to words. Here's why that changed everything.

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