Isekai (Japanese: 異世界, transl. "different world" or "otherworld") is a genre of speculative fiction. It includes novels, light novels, films, manga, anime and video games that revolve around a displaced person or people who are transported to and have to survive in another world, such as a fantasy world, virtual world, or parallel universe. Usually sent via being hit by a truck, hence the pic.
Non anime examples:
Jumanji (the new ones)
Alice in wonderland
Tron
The wizard of Oz