<?php
    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From: yoursite.com';
    $to = 'contact@yoursite.com';
    $subject = 'Customer Inquiry';
    $body = "From: $namen E-Mail: $emailn Message:n $message";

    if ($_POST['submit']) {
        if (mail ($to, $subject, $body, $from)) {
            echo '<p>Your message has been sent!</p>';
        } else {
            echo '<p>Something went wrong, go back and try again!</p>';
        }
    }
?>

error_reporting(-1);
ini_set('display_errors', 'On');
set_error_handler("var_dump");

$headers = array("From: from@example.com",
    "Reply-To: replyto@example.com",
    "X-Mailer: PHP/" . PHP_VERSION
);
$headers = implode("rn", $headers);
mail($to, $subject, $message, $headers);

$headers = array("From from@example.com", // missing colon
    "Reply To: replyto@example.com",      // missing hyphen
    "X-Mailer: "PHP"/" . PHP_VERSION      // bad quotes
);

$to = 'user@example.com';
// other variables ....
mail($recipient, $subject, $message, $headers); // $recipient should be $to

mail('user@example.com', $subject, $message, $headers);

ini_set("mail.log", "/tmp/mail.log");
ini_set("mail.add_x_header", TRUE);

$header = "From: noreply@example.comrn";
$header.= "MIME-Version: 1.0rn";
$header.= "Content-Type: text/html; charset=ISO-8859-1rn";
$header.= "X-Priority: 1rn";

mail($to, $subject, $message, $header);

function send_mail($email, $recipient_name, $message='')
{
    require("phpmailer/class.phpmailer.php");

    $mail = new PHPMailer();

    $mail->CharSet="utf-8";
    $mail->IsSMTP();                                      // set mailer to use SMTP
    $mail->Host = "mail.example.com";  // specify main and backup server
    $mail->SMTPAuth = true;     // turn on SMTP authentication
    $mail->Username = "myusername";  // SMTP username
    $mail->Password = "p@ssw0rd"; // SMTP password

    $mail->From = "me@walalang.com";
    $mail->FromName = "System-Ad";
    $mail->AddAddress($email, $recipient_name);

    $mail->WordWrap = 50;                                 // set word wrap to 50 characters
    $mail->IsHTML(true);                                  // set email format to HTML (true) or plain text (false)

    $mail->Subject = "This is a Sampleenter code here Email";
    $mail->Body    = $message;
    $mail->AltBody = "This is the body in plain text for non-HTML mail clients";
    $mail->AddEmbeddedImage('images/logo.png', 'logo', 'logo.png');
    $mail->addAttachment('files/file.xlsx');

    if(!$mail->Send())
    {
       echo "Message could not be sent. <p>";
       echo "Mailer Error: " . $mail->ErrorInfo;
       exit;
    }

    echo "Message has been sent";
}

$headers  = "MIME-Version: 1.0" . "rn";
$headers .= "Content-type: text/html; charset=iso-8859-1" . "rn";
$headers .= "From: ". $from. "rn";
$headers .= "Reply-To: ". $from. "rn";
$headers .= "X-Mailer: PHP/" . phpversion();
$headers .= "X-Priority: 1" . "rn";

mail('email@gmail.com', $subject, $message, $headers)

<?php
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From: yoursite.com';
$to = 'contact@yoursite.com';
$subject = 'Customer Inquiry';
$body = "From: $namen E-Mail: $emailn Message:n $message";

$headers .= "MIME-Version: 1.0rn";
$headers .= "Content-type: text/htmlrn";
$headers = 'From: from@example.com' . "rn" .
'Reply-To: reply@example.com' . "rn" .
'X-Mailer: PHP/' . phpversion();

mail($to, $subject, $message, $headers);

$config = Array(
        'protocol' => 'smtp',
        'smtp_host' => 'mail.domain.com', //your smtp host
        'smtp_port' => 26, //default port smtp
        'smtp_user' => 'name@domain.com',
        'smtp_pass' => 'password',
        'mailtype' => 'html',
        'charset' => 'iso-8859-1',
        'wordwrap' => TRUE
);
$message = 'Your msg';
$this->load->library('email', $config);
$this->email->from('name@domain.com', 'Title');
$this->email->to('emaildestination@domain.com');
$this->email->subject('Header');
$this->email->message($message);

if($this->email->send())
{
   //conditional true
}

<?php
    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From: yoursite.com';
    $to = 'contact@yoursite.com';
    $subject = 'Customer Inquiry';
    $body = "From:" .$name."rn E-Mail:" .$email."rn Message:rn" .$message;

if (isset($_POST['submit']))
{
if (mail ($to, $subject, $body, $from))
    {
        echo '<p>Your message has been sent!</p>';
    }
else
    {
        echo '<p>Something went wrong, go back and try again!</p>';
    }
}

?>

$name = $_POST['name'];
$email = $_POST['email'];
$reciver = '/* Reciver Email address */';
if (filter_var($reciver, FILTER_VALIDATE_EMAIL)) {
    $subject = $name;
    // To send HTML mail, the Content-type header must be set.
    $headers = 'MIME-Version: 1.0' . "rn";
    $headers .= 'Content-type: text/html; charset=iso-8859-1' . "rn";
    $headers .= 'From:' . $email. "rn"; // Sender's Email
    //$headers .= 'Cc:' . $email. "rn"; // Carbon copy to Sender
    $template = '<div style="padding:50px; color:white;">Hello ,<br/>'
        . '<br/><br/>'
        . 'Name:' .$name.'<br/>'
        . 'Email:' .$email.'<br/>'
        . '<br/>'
        . '</div>';
    $sendmessage = "<div style="background-color:#7E7E7E; color:white;">" . $template . "</div>";
    // Message lines should not exceed 70 characters (PHP rule), so wrap it.
    $sendmessage = wordwrap($sendmessage, 70);
    // Send mail by PHP Mail Function.
    mail($reciver, $subject, $sendmessage, $headers);
    echo "Your Query has been received, We will contact you soon.";
} else {
    echo "<span>* invalid email *</span>";
}

if ($_POST['submit']) {
    $success= mail($to, $subject, $body, $from);
    if($success)
    {
        echo '
        <p>Your message has been sent!</p>
        ';
    } else {
        echo '
        <p>Something went wrong, go back and try again!</p>
        ';
    }
}

try this
<?php
$to = "somebody@example.com, somebodyelse@example.com";
$subject = "HTML email";

$message = "
<html>
<head>
<title>HTML email</title>
</head>
<body>
<p>This email contains HTML Tags!</p>
<table>
<tr>
<th>Firstname</th>
<th>Lastname</th>
</tr>
<tr>
<td>John</td>
<td>Doe</td>
</tr>
</table>
</body>
</html>
";

// Always set content-type when sending HTML email
$headers = "MIME-Version: 1.0" . "rn";
$headers .= "Content-type:text/html;charset=UTF-8" . "rn";

// More headers
$headers .= 'From: <webmaster@example.com>' . "rn";
$headers .= 'Cc: myboss@example.com' . "rn";

mail($to,$subject,$message,$headers);
?>

$mail->SMTPDebug = 2;

$myText = (string)$myVar;

<?php

    error_reporting(0);
    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From: yoursite.com';
    $to = 'contact@yoursite.com';
    $subject = 'Customer Inquiry';
    $body = "From: $namen E-Mail: $emailn Message:n $message";


    if ($_POST['submit']){
                if (!(empty($_POST['name']))) {
                        if (!(empty($_POST['email']))){
                            if (!(empty($_POST['message']))){
                                mail ($to, $subject, $body, $from);
                                echo '<p>Your message has been sent!</p>';
                            }else{
                                echo '<p>Fill your message please.</p>';}
                        }else {
                            echo '<p>Fill your email please.</p>';}
                }else{
                    echo '<p>Fill your name please.</p>';}
    }else{
            echo '<p>Fill the form.</p>';}
?>

<html>
    <form method="post" action="?">
        <table>
            <tr><td>Name</td><td><input type='text' name='name' id='name'/></td></tr>
            <tr><td>Email</td><td><input type='text' name='email' id='email'/></td></tr>
            <tr><td>Message</td><td><input type='text' name='message' id='message'/></td></tr>
            <tr><td></td><td><input type='submit' name='submit' id='submit'/></td></tr>
        </table>
    </form>
</html>

$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From: yoursite.com';
$to = 'contact@yoursite.com';
$subject = 'Customer Inquiry';
$body = "From: $namen E-Mail: $emailn Message:n $message";

require 'mail/swift_required.php';

$message = Swift_Message::newInstance()
    // The subject of your email
    ->setSubject('Jane Doe sends you a message')
    // The from address(es)
    ->setFrom(array('jane.doe@gmail.com' => 'Jane Doe'))
    // The to address(es)
    ->setTo(array('frank.stevens@gmail.com' => 'Frank Stevens'))
    // Here, you put the content of your email
    ->setBody('<h3>New message</h3><p>Here goes the rest of my message</p>', 'text/html');

if (Swift_Mailer::newInstance(Swift_MailTransport::newInstance())->send($message)) {
    echo json_encode([
        "status" => "OK",
        "message" => 'Your message has been sent!'
    ], JSON_PRETTY_PRINT);
} else {
    echo json_encode([
        "status" => "error",
        "message" => 'Oops! Something went wrong!'
    ], JSON_PRETTY_PRINT);
}