<?php

    /*"" (an empty string)
      0 (0 as an integer)
      0.0 (0 as a float)
      "0" (0 as a string)
      NULL
      FALSE
      array() (an empty array)*/

$anEmptyString = "";
empty($anEmptyString);
if(empty($anEmptyString) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";         //line break

$anIntegerNumber = 0;
empty($anIntegerNumber);
if(empty($anIntegerNumber) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";         //line break

$aFloatNumber = 0.0;
empty($aFloatNumber);
if(empty($aFloatNumber) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";       //line break

$aZeroValuedString = "0";
empty($aZeroValuedString);
if(empty($aZeroValuedString) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";        //line break

$aNULL = NULL;
empty($aNULL);
if(empty($aNULL) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";        //line break

$aBooleanFALSE = FALSE;
empty($aBooleanFALSE);
if(empty($aBooleanFALSE) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";        //line break

$anEmptyArray = array();
empty($anEmptyArray);
if(empty($anEmptyArray) == TRUE){
    echo "TRUE";
} else{
    echo "FALSE";
}
echo "<hr>";       //line break

?>