What is the importance of "action" attribute in a html form?

Question

which software (html/css/js..etc etc) is required to create website like www.livebooks.com or Photoshelter.com (DIY: do it yourself).
for Frontend and backend both??

Answer 1

Description

A form is useless unless some kind of processing takes place after the form is submitted. The action attribute is used to inform the browser what page (or script) to call once the "submit" button is pressed.

Example

Here, the action attribute tells the browser to send the form data to a form-handling PHP page (which will presumably convert the form data to something more email-friendly):

<form action="form-to-email.php" method="post"
    accept-charset="windows-1252">
  <div>
    <label for="txtname">Name:</label>
    <input type="text" name="txtname" id="txtname"/>
  </div>
 ⋮
</form>

Value

This element takes as its value a URL to a document that may be on the same server (for example, a shared CGI folder that has various form-processing scripts), or even a page or script on an entirely separate server (perhaps a free form-handling service).

Answer 2

The purpose of the HTML action attribute is to specify the URL of a form processor (for example a PHP script which handles the form data).

That attribute is store the path at where Form data is handled.

<form action="Home.html">
        //form elements write hear.
</form>

In example action's value is Home.html so form data is handled at that page .