Hi guys, I'm new here and I need help for my final exam. My idea is to make traffic light detector who will recognize red and green color and through the sound signal will give information about the color of the traffic light, which will be helpful for blind people. Can you please help about what elements I need and also about the code. Thanks 
People here are not going to write your exam paper for you or otherwise help you to cheat.
If you have a program that you are having a problem with then post it and tell us in detail what it actually does and what you want it to do that is different.
...R
The idea is that you research it - look at sensor technology , what you can buy , advantages and disadvantages and therefore why you choose a particular item .
Asking on a forum = 0/10 and does set you up for your life in a job.
Hi,
Welcome to the forum.
Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html .
Can you tell us your electronics, programming, arduino, hardware experience?
We as a general rule do not supply code for a problem, but help the coder with code he has attempted.
Have you looked at what is available to sense colours?
google ** arduino colour sensor**
You will find many suggestions and examples that will give you the basics, faster than we can in "to" and "frowing" on the forum.
Thanks.. Tom...
hammy:
Asking on a forum = 0/10 and does set you up for your life in a job.
How do you plan to detect whether a traffic light is red or green?
How do you plan to have your device react to the correct traffic light? They always come in groups...
After that playing the correct sound (mp3 file from DF Player) is the easy bit.