People build all kinds of things in Minecraft, from houses, to massive buildings, to entire fantasy realms. Today is the first time I've ever seen an entire country modeled in the game, and it's a 1:1 scale!
This model of Denmark takes up approximately 4000 billion blocks, and over a terabyte of disk space. The model was produced using publicly available information - such as satellite photos, maps, and more - to generate the map as accurately as possible. Originally designed for use in classrooms, this amazing map can be downloaded in 10 square-kilometer sections, just in case you don't have the drive space for the whole country.
They are kind of like virtual currency! But you cant really spend them on anything, its a way to keep score and track of everyone on the site. The more you use things and click links the more credits you get, and the higher up on top scores list you go.
Characters allowed are A-Z 0-9 . and spaces. everything else will be removed.