Html box to txt save

Hello. How to save password, and the name, what is write text box to .txt file..
Code is here. I want a recording of the text in the box to txt file. Thanks.
Code is here

Code:

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        <div class="contact_form">
                                                <form method="post">
                                                        <input value="Kasutaja_Nimi" title="Kasutaja_Nimi" style="width: 225px;" name="Nick" onclick="this.value=':" onfocus="this.select()" onblur="this.value=!this.value?'Kasutaja_Nimi':this.value;" type="text"><br>
                                        <input value="Parool" title="Parool" style="width: 225px;" name="Password" onclick="this.value='';" onfocus="this.select()" onblur="this.value=! this.value?'parool':this.value;" type="password"><br>
                                                        <br><button class="button black" type="submit" name="Login" value="Submit">Logi sisse</button>
                                                </form>

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Image is here.
http://i1083.photobucket.com/albums/...psbdf0f16c.jpg