** 
Exponentiation 

+    *  / 
Addition, subtraction, multiplication, division 
% 
Modulo division 

&    ^ 
Bitwise AND, bitwise OR, bitwise exclusive OR 

>>  << 
Bitwise shift right, bitwise shift left 

  && 
Logical OR, logical AND 

. 
Concatenation of two strings 

x 
Returns a string or array consisting of the left operand (an array or a string) repeated the number of times specified by the right operand. 
All of the above operators have an associated assignment operator, e.g., .=
> 
Dereference operator 

\ 
Reference (unary) 

!  ~ 
Negation (unary), bitwise complement (unary) 
++   
Autoincrement (magical on strings), autodecrement 
==  != 
Numeric equality, inequality 
eq  ne  String equality, inequality 
<  > 
Numeric less than, greater than 
lt  gt  String less than, greater than 
<=  >= 
Numeric less (greater) than or equal to 
le  ge 
String less (greater) than or equal to 
<=>  cmp 
Numeric (string) compare. Returns 1, 0, or 1. 
=~  !~ 
Search pattern, substitution, or translation (negated) 
.. 
Range (scalar context) or enumeration (array context) 

? : 
Alternation (ifthenelse) operator 

, 
Comma operator, also list element separator. You can also use => 

not 
Lowprecedence negation 

and 
Lowprecedence AND 

or  xor 
Lowprecedence OR, exclusive OR 
All Perl functions can be used as list operators, in which case they have either very high or very low precedence, depending on whether you look at the left or the right side of the operator. Only the operators not, and, or, and xor have lower precedence.
A "list" is a list of expressions, variables, or lists. An array variable or an array slice may always be used instead of a list.
Parentheses can be added around the parameter lists to avoid precedence problems.