A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.
Version tags should be used for questions that apply to a version only, not to merely say what version a site is using.
Use it for questions about facilities for informing users of changes on a site, such as changes to nodes or taxonomies.
Full copies of Drupal that include Drupal Core, along with additional software are called, in Drupal terminology, distributions.
Use it for the module for running a group of affiliated sites from one installation and a single shared database.
Use it for the service that provides payment processing for e-commerce transactions.
Use it for questions about various types of logs in Drupal, including the ones shown in /admin/reports.
The act of saving files, data, or applications to a secondary media is called backing up.
Use it for questions about the services provided by Drupal.org.
Use it for questions about modal popup dialogs, including the overlay implemented in the Drupal 7 Overlay module.
Use it for questions on the module which allows users to earn and use points through various activities: the Userpoints module.
Use it for questions about the core API that allows developers to split a big task in several minor chunks or batches.
A specially written PHP callback whose parameters are configured through the web is, in Drupal terminology, an action.
Use it for questions about deployment: staging content, managing and syncing sites across multiple servers.
Use it for questions about using any of the charting modules or libraries in Drupal.
Drupal has modules for either helping advertising or blocking unsolicited advertising posted as comments or content.
Installation profiles combine core Drupal, contributed modules, themes, and pre-defined configuration into one download.
Use it for questions related to the Group module, not the Organic Groups module.
Use it for questions about the suite of modules for managing content inside Drupal: the Workbench project.
Use it for questions about Google Analytics integration with Drupal website.
Privatemsg allows your site's visitors to send private messages to each other.
Use it for questions about HTTP requests, sending and receiving requests, status codes and more.
Use it for questions about the queue of messages displayed to the client.
Use it for questions about the Drupal Bootstrap base theme.
The process to merge files together to improve a site performance with less server requests is called file aggregation.
Drupal allows a restrict set of users to access the site when maintenance tasks run: the maintenance mode.
Use it for questions about implementing the software design pattern that implements inversion of control.
A challenge-response test used for determining human users is called CAPTCHA.
Use it for questions about the set of Drupal modules that helps you maintain your Drupal sites: Aegir.
CiviCRM helps organizations grow and sustain strong relationships over time.
Use it for questions about the free Mac or Windows based AMP made available from Acquia.