connect to sql

<?php
if($_GET["regname"] && $_GET["regemail"] && $_GET["regpass1"] && $_GET["regpass2"] )
{
if($_GET["regpass1"]==$_GET["regpass2"])
{
$servername="localhost";
$username="root";


$conn= mysql_connect($servername,$username)or die(mysql_error());
mysql_select_db("test",$conn);
$sql="insert into users (name,email,password)values('$_GET[regname]','$_GET[regemail]','$_GET[regpass1]')";
$result=mysql_query($sql,$conn) or die(mysql_error());
print "<h1>you have registered sucessfully</h1>";

print "<a href='index.php'>go to login page</a>";
}
else print "passwords doesnt match";
}
else print"invaild data";
?>


Hi guys, trying to connect to a data base and having some trouble. Do I simple just put into the above

$password="password";

I have tryed this and I get and error message unable to connect.

thanks