Both Bash and PHP use a single sigil ($) to denote variables. But in Perl, sigils also kind of denote the type of the variable (Scalar, array, hash, subroutine

Both Bash and PHP use a single sigil ($) to denote variables. But in Perl, sigils also kind of denote the type of the variable (Scalar, array, hash, subroutine, typeglob). I say kind of because it's not quite that simple. PHP is actually closer to compiled languages like Java and C# than it is to Perl, Bash, or Python. It's mostly a static language with dynamic typing.