Para or por?

Question

The lesson doesn't seem to differentiate between these two words and the 2 quiz questions just require the same single word answer.  Is there anywhere that explains the differences in more detail please?

Answer

Hola Dave,
As explained to Innocent in this same thread there is a link a the bottom of the lesson that takes you to a different lesson using "por" not para, with a different meaning. Here is the link. Have a look.
Using por (not para) to express the originating cause or reason 
Saludos
Inma

Answer

I wrote "a fin de" because it's another correct way to say in order to, actually it's a formal way. Ahora resulta que siendo hispanohablante no sé cómo hablar mi propio idioma y una app para angloparoantes me va a enseñar...