chomp() will remove the end of line character(s).
On Windows these will be 0xOA, 0x0D.
On Unix this just 0x0D.

Perl is permissive about what it receives for a text line. chomp() will remove the end-of-line character(s) - might be 1 or might be 2 bytes.

When Perl writes a line: print "something\n"; , that \n may be one or two characters depending upon the OS and the context (network communication uses 0xOA, 0x0D - no matter what the OS) - but Perl knows about this and does the "right thing".

If I transfer a file from Windows to Unix, sometimes I need to do something like this to "convert" the file:

while (<STDIN>)
{
   chomp;         #remove line endings
   print "$_\n";  #write this OS's line ending
}
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"chomp()" is your friend as opposed to "chop()". chop() is seldom used.
The 'C' functions that read lines do the "chomp" automatically for you.
In Perl you have to do this yourself.