But what is the Fourier Transform? A visual introduction.

3Blue1Brown · 12.6M views · 2018-01-26 · 19:42

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Overview

3Blue1Brown's animated visual introduction to the Fourier Transform, showing how a signal breaks into frequency components.

On Hacker News

HN's default recommendation for understanding the Fourier transform intuitively; many say it was the explanation that made it click.

Recommended by 16 HN people across 15 months · HN mentions 2018–2025

Topics

Information theory & signal processing Recreational & visual math Pure mathematics

What people said

garbageman · 2025-10 · Strong recommendation
It's an absolutely brilliant bit of maths that breaks a complex waveform into the individual components. Kind of like taking an orchestral song and then working out each individual instrument's contribution. Learning about this left me honestly aghast and in shock that it's not only possible but that someone (Joseph Fourier) figured it out and then shared it with the world. This video does a great job explaining what it is and how it works to the layman. 3blue1brown - [VIDEO]
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TimSchumann · 2023-12 · Strong recommendation
Grant makes some amazing content. His visualization of the Fourier Transform[1] actually enabled me to understand the how it was happening behind the what was happening with one of the most used algorithms in computing. [1] [VIDEO]
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sjaak · 2023-01 · Strong recommendation
This is what made it click for me, can recommend it: 3Blue1Brown -- But what is the Fourier Transform? A visual introduction. [VIDEO]
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Sources

Video by 3Blue1Brown, played through YouTube.

HN Library · Source license

Data and selection notes

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HN Library: HackerTube export (2026-10-31) and open-index/hacker-news. Upstream summaries and classifications may contain AI errors.

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