用php发送电子邮件

Question

我正在通过php中的简单邮件功能发送邮件。我相同的代码正在另一个域上工作。这段代码没有给我任何错误。即使它也给我发送邮件成功的消息，但是收件箱或垃圾邮件仍然没收到。我不知道是否需要在服务器上进行任何配置？

$name="Demo"; 
$mail = "demo@gmail.com";
$desc="I need A game";
$course="English";
$budget="500";

echo $message = "Hello I am ".$name."<br>Email = ".$mail."<br>Budget For Project = ".$budget."<br>I need  ".$course."<br>Description Of Project<br>".$desc;
echo "<br>".$email = "From : ".$mail;
$subject = "Project Query";

$mail=mail("something@gmail.com", $subject, $message, $email);

if($mail){echo "<br><br>Mail has been sent..";}
else{echo "<br><br>Failed TO send a Mail..";}
?>`