Security on Wikipedia refers to the methods and principles we emply to guard potentially damaging actions from being abused by malicious or unqualified persons.

Sometimes pages may be protected to prevent their being vandalized. Protection is also sometimes used for other purposes, such as cooling down edit wars and enforcing a period of discussion.

Sometimes a user, an IP number or a range of IP numbers may be blocked to stop them damaging Wikipedia.

All registered users have a password which works like any login password. Your password is your way of ensuring that someone doesn't masquerade as you and perform bad edits. Please use a reasonably strong password, because this is the only way to avoid being blocked for bad edits by someone who cracks your password and pretends to be you.

Some actions on Wikipedia can only be carried out by privileged editors. The most common kind of privilege is adminship. It is especially important that privileged editors have strong passwords. Administrators, bureaucrats, checkusers, stewards and oversighters discovered to have cryptographically weak passwords will have their privileges removed on grounds of site security. This means that if your password can be cracked by someone running one of the many quite sophisticated open source password crackers available on the internet, we will take away your privilege before someone "borrows" it for malicious purposes.