PHP conditions

<?php
/*
if (condition)
  {
  code to be executed if condition is true;
  }
*/
$a = 9;
$b = 7;

if ( $a > $b ){
    echo 'A is bigger than B';
}

if ( $a < $b ){
    echo 'A is smaller than B';
}

if ( $a == $b ){
    echo 'A is equal to B';
}
echo '<br><hr>';
/*
if (condition)
 {
  code to be executed if condition is true;
 }
else
 {
  code to be executed if condition is false;
 }
*/
if ( $a > $b ){
    echo ' A is bigger than B';
}  else {
    echo 'A is smaller than B';
}

echo '<br><hr>';
/*
if (condition)
  {
  code to be executed if condition is true;
  }
else if (condition)
  {
  code to be executed if condition is true;
 }
else
  {
  code to be executed if condition is false;
 }
*/
if ( $a == $b ){
    echo 'A is equal to B';
}elseif ( $a < $b ) {
    echo 'A is smaller than B';
}  else {
    echo 'A is bigger than B';
}
echo '<br><hr>';
/*
switch (n)
{
case label1:
  code to be executed if n=label1;
  break;
case label2:
  code to be executed if n=label2;
  break;
default:
  code to be executed if n is different from both label1 and label2;
}
*/
$favcolor = 'pink';

switch ($favcolor) {
    case "red":
        echo 'Your favourate color is red';
        break;

    case "green":
        echo 'Your favourate color is green';
        break;

    default:
        echo 'None of this is your favourate color';
}