PHP - mysqli / mysql

//mysqli
<?php
$host = 'localhost';
$user = "root";
$pass = 'abc123';
$db = 'ITDB';
$sql = 'SELECT * FROM GradeTB';

$conn = mysqli_connect($host, $user, $pass, $db);

// Check connection
if (mysqli_connect_errno())
{
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$result = mysqli_query($conn, $sql);

while($row = mysqli_fetch_array($result)){
echo $row['name'].' '.$row['email'].'<br>';
}
mysqli_close($conn);

?>


//mysql
<?php
$host = 'localhost';
$user = "root";
$pass = 'abc123';
$db = 'ITDB';
$sql = 'SELECT * FROM GradeTB';

$conn = mysql_connect($host, $user, $pass) or die('could not connect to database');
mysql_select_db($db, $conn);

$result = mysql_query($sql);

while($row = mysql_fetch_array($result)){
echo $row['name'].' '.$row['email'].'<br>';
}
mysql_close($conn);

?>