Titanic.zip is a release file of the Minecraft map RMS Titanic 1:1 Replica, made for Minecraft 1.8, 1.8.1. It was published on December 15, 2014 and is 21.8 MB in size. For the full description, screenshots and every other version, visit the RMS Titanic 1:1 Replica map page.
How to install: Extract the .zip and move the world folder into .minecraft/saves; the map then appears in your Singleplayer list.