Minecraft: How to connect to a single player world.
This tutorial is a continuation of "Minecraft: How to build/make a custom single player world."
This tutorial is designed to select and play a single player world.
Assuming that you have selected 'Single Player' then selected the world with the desired name... in this case we will be selecting "Dead World" which has the attribute of being in 'Hardcore' mode.
Select either 'Play Selected World' OR you can directly click the little play icon on the image of the world... Enjoy!