In Wikipedia, there are three main areas into which admins can start working. These are protection, blocking and deletion. I'll now cover each of these areas.

Blocking

Blocking is the method by which administrators technically prevent users from editing Wikipedia. Blocks may be applied to user accounts, to IP addresses, and to ranges of IP addresses, for either a definite or indefinite time. A blocked user can continue to access Wikipedia, but is unable to edit any page, except (in most cases) their own user talk page. Talk page access and email use can also be removed.

Blocking should not be confused with banning, a formal retraction of editing privileges on all or part of Wikipedia. Blocks disable a user's ability to edit pages; bans do not. However, users who breach a ban (edit while banned) are likely to be blocked to enforce the ban.

Requesting blocks

Blocks can be requested in several areas. WP:ANI is the location for most blocks, while specialized places like WP:AIV and [[WP:UAA] are used for blocks relating to vandalism and usernames.

Common rationales for blocks

The following are some of the most common rationales for blocks.

Protection

A user may be blocked when necessary to protect the rights, property, or safety of the Wikimedia Foundation, its users, or the public.

Disruption

A user may be blocked when his or her conduct severely disrupts the project; that is, when his or her conduct is inconsistent with a civil, collegial atmosphere and interferes with the process of editors working together harmoniously to create an encyclopedia.

Open or anonymous proxies

Open proxies are not allowed on Wikipedia as they act somewhat like socks, people can use them to vandalize without being caught.

Blocking bots

Automated or semi-automated bots may occasionally not operate as intended for a variety of reasons. Bots (or their associated IP address should the actual bot not be readily identifiable) may be blocked until the issue is resolved. Bots that are unapproved, or usernames that violate the username policy due to a resemblance to a bot, are immediately and indefinitely blocked when discovered.

When blocking may not be used

Some reasons are not applicable for a block. They are as follows:

Self-requested blocks
Edit warring (as in, an administrator warring with another person can't just block the opposition)
Cooldown blocks, for a user to "Take a break". This is sometimes used as a reason, but only with others.

Unblocking

A user can request to be unblocked/shortened at his talkpage, after which uninvolved users will discuss the block and whether to unblock/not unblock the user. If he misuses this ability, he loses his talkpage accesses. There is no limit to the requests he can make.

Education and warnings

Before a block is imposed, efforts should be made to educate the user about our policies and guidelines, and to warn them when their behavior conflicts with our policies and guidelines. Everyone was new once, and most of us made mistakes. That's why when we welcome newcomers, we are patient with them, and assume that most people who work on the project are trying to help it, not hurt it. We also ask that newcomers make an effort to learn about our policies and guidelines so that they can learn how to avoid making mistakes. A variety of template messages exist for convenience, although purpose-written messages are often preferable.

Protection

Fully protected

Semi-protected

Pending changes protected (level 1)

Pending changes protected (level 2)

Create protected

Move protected

Upload protected

Permanently protected

Protected by Office

Pages can be protected by admins in the case of vandalism/edit warring. There are several types of protection, as follows:

Full protection prevents editing by everyone except administrators. Fully protected media files cannot be overwritten by new uploads.
Semi-protection prevents editing by unregistered contributors and contributors with accounts which are not autoconfirmed.
Creation protection prevents a page (normally a previously deleted one) from being recreated (also known as "salting").
Move protection protects the page solely from moves.
Upload protection protects the file from reupload, does not protect the file page from editing.
Pending-changes protection means edits are not visible to readers who are not logged in, until the edits are checked by a reviewer.

Any type of protection or unprotection may be requested at Wikipedia:Requests for page protection. Changes to a fully protected page should be proposed on the corresponding talk page, and carried out if they are uncontroversial or if there is consensus for them.

Other types of protection

Permanent protection

Shortcuts

Some areas of Wikipedia are permanently protected by the MediaWiki software. The MediaWiki namespace, which defines parts of the site interface, is fully protected; it is impossible for administrators to remove this protection. In addition, user CSS and JavaScript pages, such as User:Example/monobook.css and User:Example/cologneblue.js, are automatically fully protected. Only accounts that are associated with these pages or administrators are able to edit them. This protection applies to any user subpage with a ".css" or ".js" extension, whether an equivalent MediaWiki skin exists or not. Administrators may modify these pages, for example, to remove a user script that has been used in an inappropriate way.

Pages that are very visible, such as the Main Page or File:Wiki.png.
Pages that should not be modified for copyright or legal reasons, such as the general disclaimer or the local copy of the site copyright license.
Pages that are very frequently transcluded, such as {{tl}} or {{ambox}}, to prevent vandalism or denial of service attacks. This includes images or templates used in other highly visible or frequently transcluded pages. See Wikipedia:High-risk templates for more information.
Files are indefinitely move-protected.

Office actions

Shortcut

WP:BLACKLOCK

As outlined at Wikipedia:Office actions, pages may be protected by Wikimedia Foundation staff in response to issues such as copyright or libel. Such actions override community consensus. Administrators should not edit or unprotect such pages without permission from Wikimedia Foundation staff. A list of pages under the scrutiny of the Wikimedia Foundation can be found here.

Cascading protection

Shortcuts

Cascading protection fully protects a page, and extends that full protection automatically to any page that is transcluded onto the protected page, whether directly or indirectly. This includes templates, images and other media that are hosted on English Wikipedia. Files stored on Commons will not be protected by cascading protection, and need to be temporarily uploaded to English Wikipedia or protected at Commons.

Comparison table

The following table compares the effects on editors, of different protection tools.

Interaction of Wikipedia user groups and page protection levels
	Unregistered or newly registered	Confirmed or autoconfirmed	Extended confirmed	Template editor ^★	Admin	Interface admin	Appropriate for (See also: Wikipedia:Protection policy)
No protection	Normal editing						The vast majority of pages. This is the default protection level.
Pending changes	All users can edit Edits by unregistered or newly registered editors (and any subsequent edits by anyone) are hidden from readers who are not logged in until reviewed by a pending changes reviewer or administrator. Logged-in editors see all edits, whether accepted or not.						Infrequently edited pages with high levels of vandalism, BLP violations, edit-warring, or other disruption from unregistered and new users.
Semi	Cannot edit	Normal editing					Pages that have been persistently vandalized by anonymous and registered users. Some highly visible templates and modules.
Extended confirmed	Cannot edit		Normal editing				Specific topic areas authorized by ArbCom, pages where semi-protection has failed, or high-risk templates where template protection would be too restrictive.
Template	Cannot edit			Normal editing			High-risk or very-frequently used templates and modules. Some high-risk pages outside of template space.
Full	Cannot edit				Normal editing		Pages with persistent disruption from extended confirmed accounts.
Interface	Cannot edit					Normal editing	Scripts, stylesheets, and similar objects central to operation of the site or that are in other editors' user spaces.
^★ The table assumes a template editor also has extended confirmed privileges, which is almost always the case in practice.
Other modes of protection: Create protection Move protection Upload protection Office protection Cascade protection view talk edit

Protection by namespace

There are some rules for namespace specific protection:

Templates

Highly visible templates which are used on an extremely large number of pages or substituted with great frequency may be semi- or fully protected based on the degree of visibility, type of use, content, and other factors.

User pages

Shortcuts

User pages and subpages are protected at the user's request if there is evidence of vandalism or disruption. User talk pages are rarely protected, and are semi-protected for short durations only in the most severe cases of vandalism from IP users.

Users whose talk page is semi-protected for lengthy or indefinite periods of time should have an unprotected user talk subpage linked conspicuously from their main talk page to allow good faith comments from non-autoconfirmed users.

Deceased users

In the event of the confirmed death of a user, his or her user page, but not talk page, should be fully protected.

Retired users

Retired users may have their user pages protected upon request. Talk pages of retired editors are not usually protected except with limited duration to deal with vandalism. A user's request to have his or her own talk page protected due to retirement is not a sufficient rationale to protect the page.

Blocked users

Blocked users' user pages and user talk pages should not ordinarily be protected, as this interferes with the user's ability to contest their block through the normal process. In extreme cases of abuse, such as abuse of the {{unblock}} template, the talk page may be protected for a short time to prevent abusive editing. When required, it should be implemented for a brief period which should not exceed the length of the block or six months, whichever is shorter. Confirmed socks of registered users should be dealt with in accordance with Wikipedia:Sock#Sock_puppets_.28registered_accounts.29; their pages are not normally protected.

Deleting

Deletion of a Wikipedia article removes the current version and all previous versions from public view. Unlike page blanking, which can be performed (or reverted) by any user, deletion can be performed only by admins. Deletion is requested mainly at WP:AFD. There are also pages for redirects, miscellaneous pages, templates and images. Deletion can also be requested via WP:CSD and WP:PROD.

Reasons for deletion

Shortcut

WP:DEL#REASON

Reasons for deletion include, but are not limited to, the following:

Content that meets at least one of the criteria for speedy deletion
Copyright violations and other material violating Wikipedia's non-free content criteria
Vandalism, including inflammatory redirects, pages that exist only to disparage their subject, patent nonsense, or gibberish
Advertising or other spam without relevant content (but not an article about an advertising-related subject)
Content forks (unless a merger or redirect is appropriate)
Articles that cannot possibly be attributed to reliable sources, including neologisms, original theories and conclusions, and articles that are themselves hoaxes (but not articles describing notable hoaxes)
Articles for which thorough attempts to find reliable sources to verify them have failed
Articles whose subjects fail to meet the relevant notability guideline (WP:N, WP:BIO, WP:MUSIC, WP:CORP and so forth)
Articles that breach Wikipedia's policy on biographies of living persons
Redundant or otherwise useless templates
Categories representing overcategorization
Files that are unused, obsolete, or violate the Non-free policy
Any other use of the article, template, project, or user namespace that is contrary to the established separate policy for that namespace.
Any other content not suitable for an encyclopedia
Biographies of living persons without sources.

Alternatives

There are several alternatives to deletion of pages, these include just fixing any possible mistakes, merging another page with the questioned page and redirecting the page to a suitable target.

Other issues

Courtesy blanking of talkpage or deletion debates

Shortcut

WP:CBLANK

From time to time, a discussion will have its content hidden from view based on the judgment of the community, an administrator or another functionary. This is generally not done except under rare circumstances, where discussion may cause harm to some person or organisation. To avoid having such text in the most recent version and thus be indexed by search engines, the debate will be blanked out of courtesy. On occasion, pages in the project namespace, such as requests for adminship and requests for arbitration will be blanked as a courtesy, for reasons similar to those outlined above.

Partial deletion

It is possible for some parts of a page's history to be deleted, whilst leaving the current revision of the page intact, so that readers are unaware of the partial deletion unless they attempt to visit a deleted old page revision. Since 2010 administrators have access to the Revision Deletion tool, which makes it possible for them to remove selected old revisions of a page (and/or edit summaries or user names). The Revision Deletion policy strictly covers the circumstances in which this is permitted.

Assignment

Replace "USER" with your username.