Here's What the Data on Your Hard Drive Looks Like

Although magnetism is invisible to our eyes, it powers much of daily life. It drives the electric motors of just about anything that spins: fans, power tools, and blenders. It powers the microphones and speakers in our various gadgets. And it’s crucial for storing information – by which we don’t just mean pinning notes to the fridge. Magnetism enables you to click “save,” power down your computer, and walk away with the peace of mind that your documents, photos, and music will still be there tomorrow. How so? Your computer’s hard drive contains a magnetic disc with billions of tiny magnetic regions, known as bits. These encode all of your digital files into a binary code: a string of 1s and 0s. But unlike looking under the hood of a car to see the engine, opening up your computer’s hard drive doesn’t give you much sense of how it works. ...