Mysql which username use to connect php with db?

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…simply can´t understand mysql

1- I´ve been studying a tutorial on which a script connects to a database ;

<?
$usr = “–username–”;
$pwd = “–password–”;
$host = “localhost”;
$db = “linksdb”;

I have installed the server bundle W a m p and so far I´ve not been able to understand how to configure the MYSQL username ;
I followed a tutorial that showed how to assign a password to MYSQL but
it does not explain how to deal with username (is it root ? );
how to set a username on mysql ?

2- by means MYSQL Front 3.2 I accessed a server where I have an account , despite not being able to understand how the database server works.
I´ve not been able to decipher this riddle , so I wonder If someone could
me explain how (or recommend me a tutorial);

Cheers

RW

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