How many type of programming language can use in Unity 3D?
One simple look at the documentation (or a Google search) will reveal “JavaScript, C# and Boo/Python”.
unity uses only one language c# but editor supports high level scripting languages like javascript and boo. c++ cannot be used. but you can make dll out of c++ files and use it as plugins (pro feature.)
Unity3D supports JavaScript (exactly not, it is called UnityScript), C# and BooScript.