Here is a small overview of how (in)compatible computer operating systems are.
Normal text files end the lines as follows:
Windows: CR+LF
Linux: LF
OS X: CR

In order to convert line ends here are few tricks I extracted from this page(many thanks to the author):
http://kb.iu.edu/data/acux.html

dos2unix and unix2dos

The utilities dos2unix and unix2dos are available for converting files from the Unix command line.
In Debian install the package dos2unix (apt-get install dos2unix)
The package comes with the following tools:
dos2unix
unix2dos
mac2unix
unix2mac

To convert a Windows file to a Unix file, enter:
dos2unix winfile.txt unixfile.txt
To convert a Unix file to Windows, enter:
unix2dos unixfile.txt winfile.txt

tr

You can use tr to remove all carriage returns and Ctrl-z ( ^Z ) characters from a Windows file:
tr -d '\15\32' < winfile.txt > unixfile.txt
However, you cannot use tr to convert a document from Unix format to Windows.

awk

To use awk to convert a Windows file to Unix, enter:
awk '{ sub("\r$", ""); print }' winfile.txt > unixfile.txt
To convert a Unix file to Windows, enter:
awk 'sub("$", "\r")' unixfile.txt > winfile.txt
Older versions of awk do not include the sub function.
In such cases, use the same command, but replace awk with gawk or nawk.

Perl

To convert a Windows text file to a Unix text file using Perl, enter:
perl -p -e 's/\r$//' < winfile.txt > unixfile.txt
To convert from a Unix text file to a Windows text file, enter:
perl -p -e 's/\n/\r\n/' < unixfile.txt > winfile.txt
You must use single quotation marks in either command line. This prevents your shell from trying to evaluate anything inside.

vi

In vi, you can remove carriage return ( ^M ) characters with the following command:
:1,$s/^M//g
Note: To input the ^M character, press Ctrl-v , and then press Enter or return.

In vim, to convert to Unix; use :
set ff=unix
to convert to Windows, use:
set ff=dos