Salt is a thing that is found on the Earth.

Isolated, it occurs as a white granular compound; its chemical formula is NaCl (one sodium atom plus one chlorine atom, connected by some sort of bond). Most of the salt found on land occurs in this form.

Much of the salt on the Earth can be found dissolved in water (salt water) forming things like oceans, seas and some lakes and rivers and probably some other stuff as well.

Salt is an important constituent of a lot of food and drink. It can also be used as a condiment to accompany food.