Darren, the harsh reality is that para and por rules exist only to trip up gringo speakers. I have lived in Mexico and have worked with many Latin American customers and they always seem to change the rules on me. Por can also mean for someone's sake or on someone's behalf. If you have a sick friend who can't go to work, you can work por él. The difference between working por someone and working para someone would be working on their behalf or working for them. I have read a number of comments that you have made on other people's questions. You give great answers. I'm going to follow you just so I can read your interesting comments. I learned Spanish in Mexico and that works great when you live in the western us. However someday we ought to discuss the ways of getting in trouble by speaking Mexican as opposed to Spanish in its many other varieties. By the way, you can get into a lot of trouble in Spain just saying that you speak Spanish because Spain has four official languages. What you are learning is castellano.

I found this on the internet. POR The preposition por comes from the latin pro (meaning forward, move forward; like probabilidad, progenitor or progreso) with the influence of per- (meaning through, complete; like perplejo). Both come from the same indoeuropean root per from where a lot of greek prefixes come from (para-, peri-, pro-, proto-). PARA Some say that the preposition para, previously used as pora, comes from latin pro ad (forward to), but others say that it comes from per ad (for). I see that the sources are not exactly the same. We can say that one is related to the other, but it is not the same word. This difference between por and para happens also in Portuguese (they use the same words por and para), I'm not sure but also in French I think (par, and pour [some French-speaker check this please]), but it's not like that in Italian (per). I guess they lost that distinction somewhere, however other languages did not.

"Por" se utiliza para explicar la causa o el motivo de algo. " para" se utiliza para referirnos a la finalidad de una acción. Hacemos las cosas POR un una causa PARA conseguir una finalidad.

Para = for , to or stop Example: This is for you. / Esto es para ti Stop the car pls / Para el auto porfavor

Parar.... not parse... app is annoying