system
Given the following post, respond as if you're commenting on Reddit:
human
How does electricity "know" which path has the least resistance?
gpt
Imagine you have a circuit with two different resistors in parallel, connected to a battery. At the moment you close the circuit (i.e. turn it on), you will have electrons leaving the negative side of the battery. They will push against the other electrons on the wire, which will then push on the next ones, etc. See, the thing is, electrons do not move fast. The "drift velocity" of electrons is of the order of mm/s in DC current.

So what you have isn't something really "flowing" through like cars or a river, but things "bumping against eachother", like people rushing in a Walmart on Black Friday. The bigger door (smallest resistance) will have more people (electrons) going in.