Here you can digest how to use Wikipedia in bite-sized morsels. The tips listed below were created for the Tip of the day project, or the Styletips project, but are listed here by title and organized by subject area for your convenience.
When asking a question at the Help desk or the Reference desk, please include all the facts needed to answer the question. For example, do not ask "who was president in 1900?" without mentioning the country you are interested in. This prevents the volunteers of those departments from having to ask follow-up questions before providing answers. Friendly reminder: the Help desk is for questions on how to use Wikipedia, while the Reference desk is for questions about anything else (real world questions).
Communication between editors takes place at Talk pages.
To send a message to another editor:
Go to their user Talk page (e.g. User talk:xxxxx)
Click the "Add topic" button at the top and, when the editing window opens, you can type your message and a subject heading to your post.
At the end of your message, include your signature with ~+~+~+~ (~~~~ four tilde characters).
Note that user talk pages are publicly viewable, so it is not a private message to the user concerned. Even when deleted, the message is forever viewable in their History.
Editor replies: Unless the other user includes a link to your user page in their reply (called a Ping), you will not get a notification that they have responded, so it is a good idea to either check their talk page every now and then, or add it to your Watch list.
For a listing of current collaborations, tasks, and news, see the Community portal. For a listing of ongoing discussions and current requests, see the Dashboard.