Created Introduction (markdown)

Introduction.md

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+# Introduction to Biosphere2
+
+There are two types of expressions in Biosphere2:
+* Expressions that create new locations/vectors
+* Expressions that transform locations/vectors
+
+The usual workflow is that you first create a bunch of locations or vectors. In a second step you apply some transformation to them. And in a final step you do something with them. This is best shown by an example:
+```
+set {_circle::*} to circle at player with radius 1 and density 5 #creation step
+set {_bigcircle::*} to {_circle::*} scaled at player by 2 #transformation step
+show happy villager at {_bigcircle::*} #do something with your locations
+```
+The result looks like this:
+
+![](https://i.imgur.com/jaZK9KS.png)