I need to attach a rotary encoder to an arduino. The rotary encoder has 3 metal prongs that I need to attach wires to.
This picture explains exactly what I need:
What type of wire attachment is that? What should I search for to buy?
Those wires have been soldered to the pins of the encoder. Then each solder joint has been protected by a short length of heat-shrink tubing.
So you want to search for a soldering iron, solder, and heat-shrink tubing. The heat-shrink can be activated by placing it against the tip of the soldering iron, but much better results are produced by getting a heat gun, which produces a stream of hot air.