Further to Laurent_R's post:   Here are some more variants for scalar syntax; these generalize to all variable types:

c:\@Work\Perl\monks>perl -le
"use warnings;
 use strict;
 ;;
 my $var = 10;
 my $hard_ref = \$var;
 sub func { return $var; }
 sub func_ref { return \ $var; }
 ;;
 print
   qq{arbitrary whitespace within the curlies: ${  var  }apples \n},
   qq{dereference of hard reference: ${  $hard_ref  }apples \n},
   qq{deref of ref to function return value: ${  \ func()  }apples \n}
+,
   qq{deref of function returning ref: ${  func_ref()  }apples \n},
   qq{deref of ref to expression result: ${ \(11 + func()) }apples \n}
+,
   ;
 ;;
 no strict 'refs';
 ;;
 our $name = 'road';
 my $soft_ref = 'name';
 ;;
 print
   qq{dereference of symbolic reference: ${ $soft_ref }apples \n},
   qq{quoted literal symbolic identifier: ${  'name'  }apples \n},
   ;
"
arbitrary whitespace within the curlies: 10apples
dereference of hard reference: 10apples
deref of ref to function return value: 10apples
deref of function returning ref: 10apples
deref of ref to expression result: 21apples

dereference of symbolic reference: roadapples
quoted literal symbolic identifier: roadapples
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This looks to be mostly a bunch of examples of references, but I think of an expression like  ${ symbol_name } as being a dereference of a literal symbol name, so there's a natural transition to a broader consideration of references. See perldata and perlref.

Some questions for consideration:

• What happens if the  no strict 'refs'; statement before the symbolic reference examples is removed?
• If the package-global  our $name ... ; variable is made a lexical (my) variable, e.g.,
      my $name = 'road';
  what happens?
• Why are symbolic references Officially Frowned Upon? (hint)