Man discovered fire and invented the stove. Man discovered electricity and invented the light bulb. What is the difference between discovery and invention? What are other discoveries that lead to inventions?
You discover something that is already there, but for some reason hidden, hard to find, hard to comprehend. You invent something that has not existed before.
The distinction is easy to understand in the case of electricity and light bulbs. But whether the fundamental laws of nature (e.g., the Laws of thermodynamics) were discovered (= they exist independent of mankind) or invented (= we made them in order to interpret some experiments, happily ignoring their unavoidable errors) is a matter of philosophical or even religious speculation.
Discovery is known as the act of detecting something that already preexists and has been around over a long period of time. Invention is using objects, ideas or theories that are already preexisting in order to create a new object, ideas or theories that are not in existence yet.