The world we live in was a very different place millions of years ago. Most of the organisms we know now did not exist. Instead, dinosaurs lived all over the Earth. We know this from fossil records.
Fossils are the remains of dead plants and animals that turned into stone over millions of years. Some species, like the horse, have changed significantly over time and we know this because we have a complete fossil record of the horse. This is called evolution. We do not have fossil records for all organisms.
Creationists took advantage of the lack of fossils for all organisms to oppose the concept of evolution; they support the idea that organisms were created.
There are two main theories of evolution, but the one that Charles Darwin developed is the one that was accepted widely and is still believed. However, all theories of evolution have a common explanation behind them and they are related to the organisms being adapted to their environment so they can survive.
Let's explore evolution into more depth by going through some questions.