A user account was created.
The module should save its custom additions to the user object into the database.
$edit: The array of form values submitted by the user.
$account: The user object on which the operation is being performed.
$category: The active category of user information being edited.
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_user_insert(&$edit, $account, $category) {
db_insert('mytable')
->fields(array(
'myfield' => $edit['myfield'],
'uid' => $account->uid,
))
->execute();
}