What is this field: input type=hidden?

[morde]

Hello! Help me clear the code. I started studying php in Popov's lesson, all clear, but in HTML, there's a piece of website code missing:

<div class="formm" width:"80%">
<p class="form3">Подписывайтесь на нашу рассылку и получайте свежие уроки, статьи и новости, прямо в свой почтовый ящик!</p>
<form action="" method="post" name="SR_form" target="_blank">
<input type="hidden" name = "version" value="1">
<input type="hidden" name = "tid" value="34769">
<input type="hidden" name = "uid" value="27025">
<input type="hidden" name = "charset" value="windows-1251">
<input type="hidden" name = "lang" value="1">
<input type="hidden" name = "did[]" value="9267">
<p class="form1">Имя на русском:</p>
<input type = "text" name = "field_email" size = "20" value = "" maxlength = "50" style: border = "1px" #C5C5C5>
 <p class="form1">Email адрес:</p>
 <input type = "text" name = "field_email" size = "20" value = "" maxlength = "50" style: margin = "0px"; padding = "0px">
 <p "style = margin:5px; margin-top:"10px"; padding:0px;">
 <input type = "submit" name"SR_submitButton" value = "Подписаться" style = "font-family:Verdana, sans-serif" >
 </p>
</form>
</div>

Exactly:

<input type="hidden" name = "version" value="1">
<input type="hidden" name = "tid" value="34769">
<input type="hidden" name = "uid" value="27025">
<input type="hidden" name = "charset" value="windows-1251">
<input type="hidden" name = "lang" value="1">
<input type="hidden" name = "did[]" value="9267">

Is this some invisible field? What is it for?

And in the CSS, the code is clear on this point:

html>body #coolmenu a{ 
    width: auto;
}

Is that supposed to mean "in the beards"? Thank you.

[simrah]

http://htmlbook.ru/html/input/type

I'll add to the description that these fields are used to: check, send or store any data you need, which you will extract or using the same PHP in these fields.

html linebody hak for type IE baroozes