[toutoutastro]

It's in python I think.

[hobin]

It's possible to write Python-scripts to use in Blender. Blender itself, however, is written in C.

[pestaa]

Blender embeds a custom Python interpreter for its GUI and plugins.

[jfaucett]

ok, to wrap things up I downloaded the source, hobin and pestaa are right on - its c with an embedded python interpreter for writing your own scripts.

[stewie2]

i told u