<?php
$cars = array("Volvo", "BMW", "Toyota");
echo "My car is a {$cars[0]}";
?>

<?php
$color = "red";
$color = "green";
echo "$color";
?>

<?php
$color1 = "red";
$color2 = "green";
echo "$color1" . "$color2";
?>

<?php
$color1 = "red";
$color2 = "green";
echo "$color1" + "$color2";
?>

<?php
 # echo "Hello world";
 echo "# Hello world"; 
?>

<?php
$color1 = "1";
$color2 = "1";
echo "$color1" + "$color2";
?>

<?php
$color1 = "red";
$color2 = "1";
$color3 = "grey"
echo "$color1" + "$color2" . "$color3";
?>

<?php
$color1 = "red";
$color2 = "red";
echo "$color1" + "$color2";
?>

<?php
$color1 = "red";
$color2 = "1";
echo "$color1" + "$color2";
?>

<?php
echo "This", "was", "a", "bad", "idea";
?>

<?php
echo "This"."was"."a"."bad"."idea";
?>

<?php
echo "This","was"|"a","bad"."idea";
?>

<?php
echo "echo "Hello World"";
?>

<?php
<?php
echo "Hello world";
?>
?>

<?php
"Hello World"
?>

<?php
print_r "Hello world"
?>

<?php
$color = red;
echo "$color";
?>

<?php
$color = red;
echo "$color" . red ;
?>

<?php
$color1 = red;
$color2 = green;
echo "$color1"."$color2";
?>