Logging in is not required for viewing pages, and not even for editing them. However, it provides additional features, and in general projects recommend it.
Creating a user account means that you supply a username (your real name or a nickname) and a password. The system will reject a username that is already in use. A user account is created only once. You are then "logged in". Next time you log in you supply your username again and demonstrate with the password that you are the same person.
Edits you make are recorded under your username. If you are not logged in your edits are recorded under your IP address.
Why log in?
You don't have to log in to read any public MediaWiki wiki. You don't even have to log in to edit, normally: anyone can edit almost any page, even without logging in.
However, it's still a good idea to log in, for several reasons:
- Other users will be able to recognize you by your username when you make changes to pages. As a "name" an IP address is somewhat clumsy. Also, if you use computers at different locations (home, office, internet cafe, etc.) you have a different IP-address in each case; even in the same location, depending on the Internet connection, the IP-address may be different each time. Therefore a username is better to maintain an identity.
- You will have your own user page where you can write a bit about yourself, and a user talk page which you can use to communicate with other users.
- You will be able to mark an edit as minor, which avoids inconvenience for other users.
- You will be able to keep track of changes to modules you are interested in using a watchlist.
- You don't have to give your email address if you don't want to. But if you choose to give an email address, you will be able to do the following:
- reset your password if you forget it,
- receive automatic notifications of certain events, if set in your preferences,
- receive emails from other users if so set in your preferences (the user who emails you will not know your email address),
- email other users and administrators if they want as above (your email address will be disclosed on any email you send).
- You will be able to set your own preferences, to change things such as:
- the number of pages displayed in Recent changes
- the fonts, colors and layout of the site, by using different skins.
How to log in
First, make sure that your browser accepts cookies. Some browsers can accept or reject cookies from individual sites; users of these should configure the browser to accept cookies from each wiki you plan to edit, such as wikipedia.org.
Click on the "Đăng nhập" link at the top right of the page. You will then be prompted to enter your username and password. If you haven't logged in before, you will need to use the link provided to create an account. You may give your email address if you like.
If you check the box "Giữ trạng thái đăng nhập", you will not have to give your password again when you access that MediaWiki wiki from the same computer. This feature will only work if your password was not generated by the MediaWiki software.
returnto URL parameter specifies the page to redirect back to after logging in.
Log in problems
If you appear to be able to log in, but as soon as you try to look at a page you appear logged out again, it is very likely to be a cookie problem. If you are certain that cookies are enabled, make sure that you haven't inadvertently listed the wiki's domain on a list of sites for which cookies are never allowed: this feature is available in all recent browsers. Also make sure your computer's date and time are set correctly; if they are not, cookies may expire before they are supposed to. Note that some firewall and ad-blocking software may interfere with the cookie that the wiki uses to keep a person logged in.
A user may occasionally find themself "automatically" logged out in between beginning an edit and saving it, or when switching between multiple pages open in multiple windows. This can be a result of your browser's cookie, cache, or firewall settings. Regardless of the reason for the logout, the simplest solution to the problem is to check the "Giữ trạng thái đăng nhập" box. If you do this on a computer that can be accessed by more than one person (i.e. at the library, at work, at school), please find and erase your user ID cookies after your editing session.
What if I forget the password or username?
Your username is case sensitive. If you enter an email address when signing up for the account, or in your Preferences, you can make a request on the login screen for a temporary password to be sent to that address, which will allow you to retrieve your account. If you did not enter an email address, or the address was out of date, you will have to create a new account under a different username. After doing this, if a user page and user talk page were created for the old account, it is advisable to make them redirect to the equivalent pages for the new account. (To carry the content and history of these pages over to the new location, you may be able to use the "move" function ─ contact an administrator if assistance is needed.)
Creating an account
To create an account, select "Đăng nhập" (top right of page) then "Mở tài khoản". You usually need only provide a username and password. Some wikis require a visual CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart). Users with text, speech, or certain old browsers will be unable to create an account if they cannot view this image. If you are unable to view captchas, contact an administrator or request an account.
You may also be unable to create an account if it contains certain symbols (particularly the '@' symbol, as well as certain non-Latin characters) or words, or if it is too similar to that of an existing user. You may then be able to request that an account is created for you by contacting an administrator, depending on the wiki's own policies and systems. If your IP address has account creation blocked, you may be able either to request to be unblocked or to request an account.
Another possibility is that you have landed on this page from a private wiki, some other method is used to manage accounts. If that is the case, contact your system administrator, to see what the processes are, to setup or access your account. One method to try, if you think this is your case, is your organization/company's domain login credentials.
Wiki families and unified login
Some projects using MediaWiki software form a family in the sense that one logs in to the family as a whole; the functioning of their systems can vary considerably. If you are interested in one of Wikimedia Foundation's wikis (such as Wikipedia), you might want to read further at: Unified login.
You can log out any time by clicking on the "Đăng xuất" link at the top right of the page. To prevent the browser from remembering your username and suggesting it to the next user of the computer, remember to delete the wiki's cookies in your browser's privacy settings. Especially if you are using a public computer, you may want to delete all of the browser's recent history (Ctrl+Shift+Del in Firefox).
Most wikis log users out automatically after a certain time. If that happens and you try to save an edit, you will normally see a warning message that you are logged out.