PHP Operators

Arithmatic

The standard +,-,*,/,%.  No exponents. There is a unary -.
$a = 1 + 2 * 3 / 4 % -5;

Comparison

The standard <, <=, ==, >=, >, and !=.  You can use <> as an alias for !=.
Note that = is assignment and == is equality.  Get them right.  What does this code do?  Hint:  It produces no error.
 
if ($a = 7) {
    echo("Yep");
}

Logical Operators

The standard &&, ||, and !.  You can also use "and", "or", and "not", but that might help code readability.

String Concatenation

The string concatenation operator is ".".  Example:  $a=$b.$c. You can also use embedded strings like this. $a="$b $c";Note the difference between echo("4" . "5"); and echo(4 . 5);

Trenary Operator

C, C++,and Perl all have this too.  Weird, yet useful.
 
$a = $b < 0: "Yes" ? "No";
if ($b < 0)
    $a = "Yes";
else
    $a = "No";

Bitwise Operators

The standard &, |, ~, and ^.  BTW, "^" means exclusive or, and "~" mans bitwise negation..   Examples:
$a = $b | 1; // What would this mean?
$a = ~$b|1;// What about this?
These are NOT a replacement for the logical operators, but you might get away with that sometimes.  I predict the computer Gods will curse you to Valhalla if you try it though.

The shifts are << and >>.   Examples:
$a = $b >> 3 + $b >> 1;  // What's this?

Error Suppression

To ignore an error, precede the line with "@".   Great way to avoid divide by zero errors.
@$a = $b / $c;
The Shortcuts
You get the standard shortcuts that C++ and Java offer.  Namely, ++, --, +=, -=, and so on.