Electromagnetism
Electric and magnetic fields are also fields. Instead of keeping track of temperature or wind speed, they tell us how much push or pull a charged particle will feel at that point in space, and which direction it will be pushed. Like wind speeds, electric fields are also vector fields, so they can be drawn as arrows. The arrows point which way a positive particle, like a proton, will be pushed if it is in the field. Negative particles, like electrons, will go in the opposite direction as the arrows. In an electric field, arrows will point away from positive particles and towards negative ones. So a proton in an electric field would move away from another proton, or towards an electron. Similar charges repel (push away from each other), while opposite charges attract (are pulled together).