A way of saying something or someone was found. Usually, it is when the masses gain knowledge of the person, product, or information. It is obviously past tense for "discover". A person that has been discovered is already known by a small group of people. Examples of a small group could be people in their neighborhood or people with specialized knowledge in a particular area. However, when a celebrity or a person of influence promotes them, that is when they are considered "discovered".

Individuals also say they discovered a product. Like when they are the first in their immediate circle to have knowledge of the product.

You could hear about a really good product from a friend out of town, then buy it and start using it. Once you introduce it to your group of friends and family and it gains popularity, you will be known as the person that discovered that product.