A similar Stack Overflow question, Good drupal books/resources for programmers/developers?, contains a lot of useful responses. Personally, if I could have only one resource, I'd want the Pro Drupal Development book.
Beyond that, check out the Examples for Developers project and/or read the code of the modules that ship with Drupal core, for examples of how to do the basics. Those modules get lots of review and are good examples of the Drupal coding standards.
A similar Stack Overflow question, Good drupal books/resources for programmers/developers?, contains a lot of useful responses. Personally, if I could have only one resource, I'd want the Pro Drupal Development book.
Beyond that, check out the Examples for Developers project and/or read the code of the modules that ship with Drupal core, for examples of how to do the basics. Those modules get lots of review and are good examples of the Drupal coding standards.