What do you think split is doing, and why are you using a scalar to store the result?

Try changing $word to @words

I'm trying to split the file.. each line is a new word

...I take in a text file (words.txt) where there is a new word each line.

If each line is one word, splitting isn't necessary. Adapting your script, you can do the following:

#!/usr/bin/env perl
use strict;
use warnings;

open my $words, '<', 'words.txt' or die $!;

while ( my $word = <$words> ) {
    print $word;
}

print "\n\n";

close $words;
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You may have noticed from the excellent responses that lexical variables (my) are used. It's best to follow this practice--even with file handles. Also, always use strict; and use warnings;. It's also best to handle open errors, in case there was a problem opening a file.

Hope this helps!

Even using @words the code in the OP will print the length of each array since the print statement is using the . operator to concatenate.

my @words = qw( this is the end );
print "words array is this long ".@words."\n";
print @words , "\n";

__END__
words array is this long 4
thisistheend
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OK took your code at face value and made some fundamental changes:

#!/usr/bin/perl

use strict;

while ($lines = <DATA>){
    $word = split "", $lines;
    
    print $word."\n";
}

print "\n\n";
exit 0;
__END__
tutor
teacher
tinker
sailor 

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$ ./fix.pl 
Global symbol "$lines" requires explicit package name at ./fix.pl line
+ 5.
Global symbol "$word" requires explicit package name at ./fix.pl line 
+6.
Global symbol "$lines" requires explicit package name at ./fix.pl line
+ 6.
Global symbol "$word" requires explicit package name at ./fix.pl line 
+8.
Execution of ./fix.pl aborted due to compilation errors.
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#!/usr/bin/perl

use strict;

while (my $lines = <DATA>){
    my $word = split "", $lines;
    
    print $word."\n";
}

print "\n\n";
exit 0;
__END__
tutor
teacher
tinker
sailor 

[download]

$ ./fix.pl 
6
8
7
8



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#!/usr/bin/perl

use strict;

while (my $lines = <DATA>){
    my ($word) = split "", $lines;
    
    print $word."\n";
}

print "\n\n";
exit 0;
__END__
tutor
teacher
tinker
sailor 

[download]

$ ./fix.pl 
t
t
t
s

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1. Remember: the function split() returns an array based on the regex designating where to split the string. In this case you pass in an empty string which causes your $lines variable to be split on every character. (was that your intention?)
2. Without the enclosing parenthesis around $word you are using an array in a scalar context which means you are going to get the length of that array as a scalar not the value of the array itself.

Hope this helps you on your way....

from perldoc -f split:

    split /PATTERN/,EXPR,LIMIT
    split /PATTERN/,EXPR
    split /PATTERN/
    split   Splits the string EXPR into a list of strings and returns 
+that
            list. By default, empty leading fields are preserved, and 
+empty
            trailing ones are deleted. (If all fields are empty, they 
+are
            considered to be trailing.)

            In scalar context, returns the number of fields found.
    ....
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Try splitting to an array, @words and printing them....

#!/usr/bin/perl
use 5.014;
# 1007352

# error here:    $word = split "", $lines;

my $lines = "foo bar baz bat read the docs; they're often helpful.";

my @word = split "", $lines;  # $word replaced with @word

say @word;
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OR (perhaps preferably)

#!/usr/bin/perl
use 5.014;
# 1007352

# error here:    $word = split "", $lines;

my $lines = "foo bar baz bat read the docs; they're often helpful.";

my @word = split " ", $lines;  # $word replaced with @word; "" replace
+d with " "

my $word;
for $word( @word) {
    say $word;
}
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Evaluating @word like so will return a number; you can put your array into double quotes:

print "@word\n";
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However, I think since your already going through the lines your better off just doing this:

while( my $line = <WORD> ){
   print $_;
}
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Update: I see now that split is the problem, and putting it into scalar context