Nanowires are thin structures measuring 0.000000001 meters in diameter, which is so thin that they essentially behave as if they only have one-dimension. This one-dimensional nature gives nanowires a ton of interesting electrical and magnetic properties, which are super useful in electronics and medical devices, especially as they are getting smaller and smaller. Nanowires can be made from a number of different materials. The grey columns in this image depict germanium nanowires grown on a silicon substrate by undergraduate students in the Chemistry 165 Harvard undergraduate course. These columns were created by a technique called glancing angle deposition, in which a germanium source is heated to its boiling point in a vacuum, causing it to evaporate. A silicon substrate is held at an angle above, and, as the germanium evaporates, it begins to deposit on the silicon. Interestingly, the morphology of the nanowires can be manipulated by adjusting the angle between the source and the substrate. By changing the morphology of the nanowires, you can tailor their electrical and magnetic properties to your devices’ needs.