Drupal core function node_save() is used to save nodes and it is frequently used to programmatically alter and save nodes' data, which includes fields (aka CCK fields) as well. If you want to update a field of a node you could do it like following
This tutorial will help you to know how you can create custom search page in drupal 7 easily. It will explain you with code snippet to explain each part the process you need.
1. Create menu items in your hook_menu().
Multiple step form which consists of multiple steps or pages is useful sometimes. It allows you to create a form workflow and helps to make your web site user-friendly and flexible. For example, you can make different contents on next pages based on user inputs from previous pages.
The key things to make a form multiple pages are setting $form_state[‘rebuild’] and $form_state[‘storage’] variables in a submit function.
Some of the site needs email as sername for their Drupal site. Email Registration module helps to get rid of that problem.
but it saves username from the email address whatever that is before @.
example : email@example.com save username as : takim.islam