Question: Why were electrons chosen to be negatively charged? Wouldn't it make more sense to call electrons positively charged because when they move they make electricity?

Jesse Dykes answered on 12 Mar 2020:

When electric circuits were first developed, they did say that charge is positive and flows forward through circuits, and worked talking about this for many decades. At the beginning there was no reason to even suspect that electricity was made up of the movement of particles, but they could tell it was a flow of some kind. It was only later in quantum physics that the electron was discovered to be responsible for the flow of electricity, and flowed the opposite direction to what they’d thought. Rather than change the maths to say which direction electricity flows, which would confuse a lot of people like engineers and electricians, they decided to say that the electron is negative. So quantum physicists are happy that they can still do maths with electron charges, and engineers are happy that they don’t have to change how they do things.