I thought game engine are something like Unity or Unreal. They have a editor with scene editor, some Physics library, some scripting editor and tools to improve the workflow of developer. Furthermore, I thought game engine should independent of the actually game.(i.e.) The game engine should not have any game logic in it.
However, I watched this game engine video and I am totally confused. https://www.youtube.com/watch?v=GK7ntA7a2vk . In the game engine video, I don't see the game engine anywhere because it seemed as though the professor developed the game straightaway.
I hope someone can explain the exact difference between a game engine and the actual game.