Music

Learn to read and play: two hundred first piano pieces for kids, Christmas carols at five levels, jazz guitar for beginners and a full music theory guide. Every piece and example plays out loud.

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Electronics

From “what is a volt?” to ten Arduino experiments, then how to measure what you’ve built with a multimeter. Plus reference pages for the battery, plug or screw in front of you.

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Radio

One cheap USB stick turns a laptop into a receiver for aircraft, ships, weather satellites and free-to-air TV. Start with what a software-defined radio is, then pick one of twelve weekend projects.

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Audio

What’s inside a WAV, FLAC or MP3 file, how a CD works, and how to get music from a computer to your speakers untouched. Plus Ironbark, our free music player that checks every song plays bit-perfect.

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The pages you look things up on. What the Moon is doing tonight, how to read the symbols in a dictionary, which pencil is which, how long division goes, and the tables for batteries, plugs and radio frequencies.

Go to Reference

Gear

Torches, watches and the things you carry. What lumens, candela and beam distance mean on a torch box, how each kind of watch keeps time and what its water rating allows, plus a free watch accuracy checker.

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Jigsaw puzzles

A method that works on any puzzle, from the border to the plain blue sky, how big each size ends up and the table you need, and how to glue and frame one you want to keep. Plus a free online jigsaw you can play with your own photo.

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Chess

How to play, with a diagram for every piece and the rules people get wrong: castling, en passant, stalemate and the draws. How to read and write the moves, what the numbers on a chess clock mean, and a free clock for your phone.

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More topics, on Learn

These don’t have a page of their own yet. Each card opens our Learn section with that topic picked.

How AI works →Why the same question gets a different answer, the technical terms in plain words, and the history of AI from ancient myths to ChatGPT. Discs, tapes and video →How a CD stores data, saving a damaged DVD, and converting VHS and cassette tapes to digital yourself. Files and encoding →WAV, FLAC and MP3, codecs and containers, getting the best sound from a computer, and how a computer knows a file isn’t broken. Inside the computer →The Turing machine, the 1936 idea behind every computer, and every screw in a PC and a laptop. Compasses and navigation →Buying a compass that works in Australia, setting the declination and finding your way.

On the way

Topics we’re writing for next.

Mechanical engineeringManual machining, welding, fabrication and engineering drawings, from our director’s trade training.No pages yet

Also on the site

Free tools →Calculators, look-ups and checkers you can use straight away in your browser. Learn →Every lesson and reference guide, with search and a filter by topic. Articles →Dated guides and opinion: AI plans in Australia, small-business tech and more. Bookshelf →The books we’ve enjoyed and keep telling people about.

Pick a topic