How is an electrolytic capacitor connected correctly?

Question

Arduino

Is the positive leg to the positive wire, and the negative leg to the negative or to the break in the positive wire (like a transistor)?

Answer 1

See what the goal is. If you need to filter out ripples in power circuits , then the first option (parallel to power).
And if you need to filter out the constant component or low frequencies (for example, in the filters of low-frequency amplifiers and acoustic systems), then into the gap.
The capacitor passes alternating current. The higher the frequency, the better the transmission. This is the basis of two different switching schemes for different purposes.