What is the use of transition map and what is "seamless transition" in UE4?

Since there is no much information about it, I thought to post it here and learn more about it. After some research I have found that it’s being used in a system called “seamless transition” which is used to load maps seamlessly. Also there is a system called level streaming which helps you load the game map sub level by sub level. I have already used level streaming in my projects. Is this “seamless transition” behave just like level streaming? or its a completely different thing?

Can “seamless transition” used in single player games or is it only for multiplayer games? Please help me to clarify these information.

Thank you.

Seamless means that the map can load without and loading screen or any delay, like Fallout 4 and skyrim when you walk. it is used in almost all games. 3D All open world games use it.

Seamless (Seamless travel) means you won’t disconnect from the server.

You can check details from here: