You use "para" when you want to say "in order to" / for the purpose of / Directed to - an object or person- /"Para ti" for you / Yo fue al cine para relajar. (for purpose of) - I went to the movie to relax. I went to London by plane. Yo fue a London pro avion. Por is used to mean "by" like in referring to a location/movement - Por el parque ; pro las called etc. - by (near) the park - specific location Where is the ____? (located). "Por el lado" - by the side. I hope this helps. You can google this as well...

Por: 1. Reason No podemos dormir por el ruido - we can't sleep because of the noise 2. Time or locate (not specific, but more less you know the time or the place) Hemos quedado por el centro - we stayed at the center Volveré a mi casa por la Navedad - I am going to come back home for Christmas 3. Method of doing something Hemos hablado por facebook - we have talked on facebook 4. Exchange or shopping Te cambio mi perro por el tuyo - I change my dog for yours Te compro eso por 15 euros - I am going to buy it for you for 15 euros Para: 1. The final result or a purpose Un vaso sirve para beber agua - A glass serves you to drink water Vamos a Madid para aprender español y pasarlo muy bien. - Let's go to Spain to learn Spanish and to have great fun. 2. If there's something that is like a destiny for you Mi amor es sólo para ti - My love is only for you. ¿Para quién es este regalo? - Who is the person who should receive this gift? 3. Opinion Para mí www.italki.com es una página web muy interesante - I think www.italki.com is an interesting web page. 4. Direction Vamos para la casa (Vamos a la casa) - Let's go home 5. Limited time El debere es para viernes - The homework is for Friday 6. Consequences (however) Para lo poco que comes, estás muy gordo. - You eat a little. However, you are very fat. I hope this helps. If you have any further questions, feel free to ask me.

http://spanish.about.com/cs/grammar/a/porpara.htm Welcome to the tricky world of prepositions.