Electrical charges lie somewhere between the dichotomy of positive and negative, and certain particles have inherent charges to them. For example, protons are positively charged and electrons are negatively charged. This concept is of incredible importance in all of the physical sciences, as well as engineering, biology, etc. A great example how electrical charge shapes the nature of life on the planet is through the water molecule. Water is simply two atoms of Hydrogen and one atom of Oxygen. However, opposite charges attract and as the Oxygen nucleus is much larger than the Hydrogen nucleus. The extreme difference in electronegativity causes the covalently shared electrons to exhibit a proclivity to orbit more so around the Oxygen nucleus, resulting in a net negative charge around the Oxygen and net positive charge around the Hydrogen. This is called polarity and this property dictates how water reacts to various elements and compounds.