Creating a form which contains two text fields and a submit button.Main aim is to save data and get the sabed values when needed. variableset() and variableget() functions to store and retrieve data.

/*
* Create a form
*/
function mymenu_settings(&$form_state)
{
    $form['mymenu_settings_form']['email'] = array(
        '#type' => 'textfield',
        '#title' => t('Enter e-mail'),
        '#size' => 50,
        '#maxlength' => 255,
        '#description' => t('This is an email field'),
        '#default_value' => variable_get('email'),
     );

     $form['mymenu_settings_form']['address'] = array(
        '#type' => 'textfield',
        '#title' => t('Enter address'),
        '#size' => 50,
        '#maxlength' => 255,
        '#description' => t('This is an address field'),
        '#default_value' => variable_get('address'),
     );

    $form['mymenu_settings_form']['save'] = array(
        '#type' => 'submit',
        '#value' => t('Save'),
        '#submit' => array('mymenu_settings_form_save_submit'),
      );

  return $form;
}

/**
 * Submit mymenu_settings_form  save action.
 */
function mymenu_settings_form_save_submit($form, &$form_state) {
    // if required to set a value that is to be used later on
     variable_set('email', $form_state['values']['email']);
     variable_set('address', $form_state['values']['address']);
     drupal_set_message(t('Saved'));
}