How browser's identify login forms?

Question

I\'m trying to find out: how browsers identify login forms in different sites?

Doesn\'t matter if I\'m acessing my GMail account or some personal project, IE/Firefox alw

Answer 1

They look for input type=password.

Answer 2

No only do they look for type=password they will also look for common input names for usernames and passwords.

For example most browsers will detect the following field names as login information.

<input name="login" type=text>
<input name="user" type=text>
<input name="username" type=text>
<input name="passwd" type="password">
<input name="pass" type="password">
<input name="password" type="password">