What is the difference between concurrent programming and parallel programming?

Question

What is the difference between concurrent programming and parallel programing? I asked google but didn't find anything that helped me to understand that difference. Could you give me an example for both?For now I found this explanation: http://www.linux-mag.com/id/7411 - but "concurrency is a property of the program" vs "parallel execution is a property of the machine" isn't enough for me - still I can't say what is what.

Answer 1

Concurrent programming is the implementation of mechanisms to avoid parts of a program from entering into conflict. For example, two processes trying to access a file.

Meanwhile, parallel programming is a way of making two or more parts of a program function simultaneously.

For example, launching a user interface while checking network connectivity.