in effect the difference is subtle and can fade into equivalence, but see it from this point of view: a list is not a Perl data type. Perl has three main variable types: scalars, arrays, and hashes. (perlintro).

In Learning Perl - third edition is stated this way:

> A list is an ordered collection of scalars. An array is a variable that contains a list. In Perl, the two terms are often used as if they're interchangeable. But, to be accurate, the list is the data, and the array is the variable. You can have a list value that isn't in an array, but every array variable holds a list

Sometimes, just to make things more foggy, you can do operations on list in the same way as you do with array:

 print +( qw(J A P H) )[2] prints P

but you cant shift a list and the doc goes: shift ARRAY but for example print accepts a list: print LIST

Another key concept is LIST in respect of context and here it overlaps with array: LIST or SCALAR context: in list context you can assign it to an array, but again, the array is the perl variable and the list is its value.

See also: What is the difference between a list and an array? and Scalars, Lists, and Arrays

L*

if split returned an array, you couldn't do something like ($word1, $word2, $word3, $word4) = split(/ /, 'This is a sentence.')

What am I missing in ...

@collect = split( / /, 'This is a sentence.' );
( $word1, $word2, $word3, $word4 ) = @collect;
print join( q[ ; ], ( $word1, $word2, $word3, $word4 );
[download]

... ?

What am I missing

The $word* variables aren't getting assigned "an array", they are getting assigned the values from the array.

@collect = split( / /, 'This is a sentence.' );	The array on the LHS means that the assigment is in list context. Split returns a list of scalars. In list context, the elements of what's on the LHS get assigned to the values from the list on the RHS, so the @collect array is populated from the values returned by split
( $word1, $word2, $word3, $word4 ) = @collect;	The (...) on the LHS mean that the assignment is in list context Per List value constructors, the @collect array gets evaluated in list context, which results in the list (on the RHS) consisting of the elements from the @collect array The assignment then happens in list context, so the leftmost item of the list on the LHS ($word1) gets assigned the value of the leftmost item from the list on the RHS, and so on
print join( q[ ; ], ( $word1, $word2, $word3, $word4 );	=> syntax error at parv.pl line 3, near ");" but with a second ) on that line to allow it to compile: the words are given list context by the parentheses (unnecessarily, because join already gives list context) join concatenates the elements of that list, using space-semicolon-space as the separator, into a string That string is then printed.

(LHS = "Left-hand side", RHS = "Right-hand side": in these cases, relative to the assignment operator =)