Let's start with easy PHP sample,
simple registration page
first you need to create a registration form page.
let's name it "registrationForm.php"
<form method="POST" action="register.php">
<table>
<tr><td>Username:</td><td><input type="text" name="username"></td></tr>
<tr><td>Username:</td><td><input type="text" name="username"></td></tr>
<tr><td>Password:</td><td><input type="password" name="password"></td></tr>
<tr><td colspan="2"><input type="submit" name="register" value="register"></td></tr>
</table>
</form>