Reducible

Reducible is a computer science channel that uses animation to explain algorithms and the ideas behind them. Uploads have been rare since 2024, but its back catalogue remains a strong resource.

Each video takes one big idea and builds it up from the basics. Smooth animations show data moving through an algorithm step by step. Topics include signal processing, graph theory, recursion and the methods used to compress images. The videos are long and thoughtful, and they reward careful watching.

Some highlights include:

This video explains the Fast Fourier Transform, an algorithm used everywhere from audio to wireless communication.

This one shows how JPEG compression shrinks photos by throwing away detail the eye barely notices.

This video sets out a five step method for solving dynamic programming problems.

The channel has around 337,000 subscribers.

Algorithms are the engine of software engineering, and signal processing is central to electronic and communications engineering. Reducible connects A level maths to the technology inside phones, cameras and maps. It suits students considering computer science, software engineering or electronic engineering at university. The videos on JPEG and PNG are a particularly good example of engineering trade-offs, where speed, file size and quality pull in different directions. Students who enjoy puzzles will also find the problem solving videos useful for coding challenges and Olympiad-style questions.