It depends on the platform.
On Windows you'll have \r\n (carriage return, new line). On Linux, OS X, and other Unix-like systems, it is just \n (new line). On Classic Mac OS (up to version 9) it is just \r (carriage return).
Probably you are using windows. The best way to deal with cross-platform texts is this:
- substitute \r\n with \r
- substitute \r with \n
This way you'll end up with just \n, whatever platform the text originated from and you'll have the benefit of uniforming line endings, because some editors do not touch unmodified lines and on saving you end up with mixed line endings, which are even worse than this.