HTML
><div class="container">
    <div class="row">
        <div class="col-md-12">
            <div class="well well-sm">
                <form>
                    <div class="row">
                        <div class="col-md-6">
                            <div class="form-group">
                                <label for="name">
                                    Name</label>
                                <input type="text" class="form-control" id="name" placeholder="Enter name" required="required" />
                            </div>
                            <div class="form-group">
                                <label for="email">
                                    Email Address</label>
                                <div class="input-group">
                                <span class="input-group-addon"><span class="glyphicon glyphicon-envelope"></span>
                                </span>
                                    <input type="email" class="form-control" id="email" placeholder="Enter email" required="required" /></div>
                            </div>
                            <div class="form-group">
                                <label for="subject">
                                    Subject</label>
                                <select id="subject" name="subject" class="form-control" required="required">
                                    <option value="na" selected="">Choose One:</option>
                                    <option value="service">General Customer Service</option>
                                    <option value="suggestions">Suggestions</option>
                                    <option value="product">Product Support</option>
                                </select>
                            </div>
                        </div>
                        <div class="col-md-6">
                            <div class="form-group">
                                <label for="name">
                                    Message</label>
                                <textarea name="message" id="message" class="form-control" rows="9" cols="25" required="required"
                                          placeholder="Message"></textarea>
                            </div>
                        </div>
                        <div class="col-md-12">
                            <button type="submit" class="btn btn-primary pull-right" id="btnContactUs">
                                Send Message</button>
                        </div>
                    </div>
                </form>
            </div>
        </div>


    </div>
</div>
PHP


<?php
if (isset($_POST["submit"])) {
    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $human = intval($_POST['human']);
    $from = 'Demo Contact Form';
    $to = 'example@bootstrapbay.com';
    $subject = 'Message from Contact Demo ';

    $body = "From: $name\n E-Mail: $email\n Message:\n $message";

    // Check if name has been entered
    if (!$_POST['name']) {
        $errName = 'Please enter your name';
    }

    // Check if email has been entered and is valid
    if (!$_POST['email'] || !filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) {
        $errEmail = 'Please enter a valid email address';
    }

    //Check if message has been entered
    if (!$_POST['message']) {
        $errMessage = 'Please enter your message';
    }
    //Check if simple anti-bot test is correct
    if ($human !== 5) {
        $errHuman = 'Your anti-spam is incorrect';
    }

// If there are no errors, send the email
    if (!$errName && !$errEmail && !$errMessage && !$errHuman) {
        if (mail ($to, $subject, $body, $from)) {
            $result='<div class="alert alert-success">Thank You! I will be in touch</div>';
        } else {
            $result='<div class="alert alert-danger">Sorry there was an error sending your message. Please try again later</div>';
        }
    }
}
?>