Simple typo

Author: papandreas42

s10_extra/documentation.md

@@ -330,5 +330,5 @@ Before getting started with this set of exercises you should have completed
 4. Make sure your documentation is published and looks as it should.
 
 This ends the module on technical documentation. We cannot stress enough how important it is to write proper
-documentation for larger projects that need to be maintained over a longer time. It is often a iterative process, but
+documentation for larger projects that need to be maintained over a longer time. It is often an iterative process, but
 it is often best to do it while writing the code.