Start your sections with header lines:

Header

New section

Subsection

Sub-subsection

= Header =

== New section ==

=== Subsection ===

==== Sub-subsection ====

A single newline has no effect on the layout. These can be used to separate sentences within a paragraph. Some editors find that this aids editing and improves the diff function.

But an empty line starts a new paragraph.

A single [[newline]]
has no effect on the layout. 
These can be used to separate
sentences within a paragraph.
Some editors find that this aids editing
and improves the ''diff'' function.

But an empty line
starts a new paragraph.

You can break lines<br>
without starting a new paragraph.

• Lists are easy to do:
  • start every line with a star
    • more stars means deeper levels

* Lists are easy to do:
** start every line with a star
*** more stars means deeper levels

1. Numbered lists are also good
   1. very organized
   2. easy to follow

# Numbered lists are also good
## very organized
## easy to follow

• You can even do mixed lists
  1. and nest them
     • like this

* You can even do mixed lists
*# and nest them
*#* like this

Definition list 

list of definitions

item 

the item's definition

; Definition list : list of definitions
; item : the item's definition

• One item per line, no hard NEWLINE.

A colon indents a line or paragraph.

A manual newline starts a new paragraph.

• This is primarily for displayed material, but is also used for discussion on Talk pages.

: A colon indents a line or paragraph.
A manual newline starts a new paragraph.

IF a line starts with a space THEN
  it will be formatted exactly 
    as typed;
  in a fixed-width font;
  lines won't wrap;
ENDIF
this is useful for:
  * pasting preformatted text;
  * algorithm descriptions;
  * program source code;
  * ascii art and chemical structures;

WARNING If you make it wide, you force the whole page to be wide and hence less readable. Never start ordinary lines with spaces.

 IF a line starts with a space THEN
   it will be formatted exactly 
     as typed;
   in a fixed-width font;
   lines won't wrap;
 ENDIF
 this is useful for:
   * pasting preformatted text;
   * algorithm descriptions;
   * program source code;
   * [[ascii art]] and chemical structures;

<center>Centered text.</center>

and this is below it.

Mainly useful for separating threads on Talk pages.

A horizontal dividing line: this is above it
----
and this is below it. 

• First letter of target is automatically capitalized.
• Internally spaces are automatically represented as underscores (typing an underscore has the same effect as typing a space, but is not recommended).

Thus the link above is to http://www.wikipedia.org/wiki/Public_transport, which is the article with the name "Public transport". See also Wikipedia:Canonization.

London has good [[public transport]].

Link to a section on a page, e.g.

answers.
(This is a piped link.)

Same target, different name: 
[[wikipedia FAQ|answers]]

Endings are blended 
into the link: [[test]]ing, [[gene]]s

Automatically hide stuff in parentheses: kingdom.

Automatically hide namespace: Village Pump.

The server fills in the part after the | when you save the page. Next time you open the edit box you will see the expanded piped link. A preview interprets the abbreviated form correctly, but does not expand it yet in the edit box. Press Save and again Edit, and you will see the expanded version. The same applies for the following feature.

Automatically hide stuff in parentheses:
[[kingdom (biology)|]]. 

Automatically hide namespace: 
[[Wikipedia:Village Pump|]].

you should sign it. You can do this by adding three tildes for your user name:

Montrealais

or four for user name plus date/time:

Montrealais 08:10 Oct 5, 2002 (UTC)

When adding a comment to a Talk page,
you should sign it. You can do this by
adding three tildes for your user name:
: ~~~
or four for user name plus date/time:
: ~~~~

exist yet.

• You can create it by clicking on the link.

• To create a new page:
  1. Create a link to it on some other page.
  2. Save that page.
  3. Click on the link you just made. The new page will open for editing.
• Have a look at how to start a page guide and Wikipedia's naming conventions.
• After creating a page, search for its title and make sure that everyone correctly links to it.

[[The weather in London]] is a page 
that doesn't exist yet.

Redirect one article title to another by putting text like this in its first line.

#REDIRECT [[Filipinas]]

Articles can be linked to a page on the same subject in another language using a link like [[language code:Title]]. It does not matter where you put these links while editing as they always show up in the same place when you save the page, but placement at the end of the edit box is recommended. See Wikipedia:Interlanguage links.

External link: 
[http://www.nupedia.com Nupedia]

• In the URL all symbols must be among: A-Z a-z 0-9 ._\/~%-+&#?!=()@ \x80-\xFF. If a URL contains a different character it should be converted; for example, ^ has to be written %5E (to be looked up in ASCII).

Or just give the URL: 
http://www.nupedia.com.

• Only images that have been uploaded to Wikipedia can be used. To upload images, use the upload page. You can find the uploaded image on the image list. See Wikipedia:Image use policy and Image markup for many more hints.
• Alternative text, used when the image isn't loaded, in a text-only browser, or when spoken aloud, is strongly encouraged. See Alternate text for images for help on choosing it.

A picture: [[Image:Wikipedia-logo-ilo.png]]

or, with alternate text

[[Image:Wikipedia-logo-ilo.png|jigsaw globe]] 

or, floating to the right side of the page. Place above the text to appear beside it. The caption is The Wikipedia logo. Use a width as wide as the image or a little wider.

<div
style="float:right;width:135px;margin:0 0 1em 1em">
[[Image:Wikipedia-logo-ilo.png|jigsaw globe]]
<small>The Wikipedia logo</small>
</div>

More at Wikipedia:Image_markup.

Clicking on an uploaded image displays a description page, which you can also link directly to: Image:Wiki.png

[[:Image:Wiki.png]]

To include links to non-image uploads such as sounds, or to images shown as links instead of drawn on the page, use a "media" link.

Sound

Image of a Tornado

[[media:Sg_mrob.ogg|Sound]]

[[media:Tornado.jpg|Image of a Tornado]]

To link to books, you can use Wikipedia:ISBN links.

ISBN 0123456789X

ISBN 0123456789X

Special:Whatlinkshere/Wikipedia:How to edit a page and Special:Recentchangeslinked/Wikipedia:How to edit a page

Emphasize, strongly, very strongly.

• These are double and triple apostrophes, not double quotes.
• Note that on almost all browsers, these have the same function as bold and italic

''Emphasize'', '''strongly''', 
'''''very strongly'''''.

• for semantic reasons, <code> should be used instead when writing computer programs

A typewriter font for <tt>technical terms</tt>.

You can use <small>small text</small> for captions.

and underline new material.

You can <strike>strike out deleted material</strike>
and <u>underline new material</u>.

Umlauts and accents:
(See wikipedia:Special characters)
è é ê ë ì í

À Á Â Ã Ä Å
Æ Ç È É Ê Ë
Ì Í Î Ï Ñ Ò
Ó Ô Õ Ö Ø Ù
Ú Û Ü ß à á
â ã ä å æ ç
è é ê ë ì í
î ï ñ ò ó ô
œ õ ö ø ù ú
û ü ÿ

è é ê ë ì í

À Á Â Ã Ä Å 
Æ Ç È É Ê Ë 
Ì Í Î Ï Ñ Ò 
Ó Ô Õ Ö Ø Ù 
Ú Û Ü ß à á 
â ã ä å æ ç 
è é ê ë ì í
î ï ñ ò ó ô 
œ õ ö ø ù ú 
û ü ÿ

Punctuation:
¿ ¡ § ¶
† ‡ • —
‹ › « »
‘ ’ “ ”

¿ ¡ § ¶
† ‡ • —
‹ › « »
‘ ’ “ ”

Commercial symbols:
™ © ® ¢ € ¥

™ © ® ¢ € ¥ 
£ ¤

Superscript: x² or x²

• The latter method of superscript can't be used in the most general context, but is preferred when possible (as with units of measurement) because most browsers have an easier time formatting lines with it.

ε₀ = 8.85 × 10⁻¹² C² / J m.

1 hectare = 1 E4 m²

Subscript: x<sub>2</sub>
Superscript: x<sup>2</sup> or x&sup2;







&epsilon;<sub>0</sub> =
8.85 &times; 10<sup>&minus;12</sup>
C&sup2; / J m.

1 [[hectare]] = [[1 E4 m²]]

α β γ δ ε ζ
η θ ι κ λ μ ν
ξ ο π ρ σ ς
τ υ φ χ ψ ω
Γ Δ Θ Λ Ξ Π
Σ Φ Ψ Ω

α β γ δ ε ζ 
η θ ι κ λ μ ν 


ξ ο π ρ  σ ς
τ υ φ χ ψ ω
Γ Δ Θ Λ Ξ Π 
Σ Φ Ψ Ω

Math characters:
∫ ∑ ∏ √ − ± ∞
≈ ∝ ≡ ≠ ≤ ≥ →
× · ÷ ∂ ′ ″
∇ ‰ ° ∴ ℵ ø
∈ ∉ ∩ ∪ ⊂ ⊃ ⊆ ⊇
¬ ∧ ∨ ∃ ∀ ⇒ ⇔
→ ↔
(See also WikiProject Mathematics)

∫ ∑ ∏ √ − ± ∞
≈ ∝ ≡ ≠ ≤ ≥ →
× · ÷ ∂ ′ ″
∇ ‰ ° ∴ ℵ ø
∈ ∉ ∩ ∪ ⊂ ⊃ ⊆ ⊇
¬ ∧ ∨ ∃ ∀ ⇒ ⇔
→ ↔

• To space things out, use non-breaking spaces - &nbsp;.
• &nbsp; also prevents line breaks in the middle of text, this is useful in formulas.

<i>x</i><sup>2</sup>&nbsp;&nbsp;&ge;&nbsp;&nbsp;0 true.

Complicated formulae:
  

• See Wikipedia:TeX markup

  
<math>\sum_{n=0}^\infty \frac{x^n}{n!}</math>

Suppressing interpretation of markup:
Link → (<i>to</i>) the [[Wikipedia FAQ]]

• Used to show literal data that would otherwise have special meaning.
• Escapes all wiki markup, including that which looks like HTML tags.
• Does not escape HTML character references.

<nowiki>Link &rarr; (<i>to</i>) 
the [[Wikipedia FAQ]]</nowiki>

Commenting page source:
not shown in page

• Used to leave comments in a page for future editors.

<!-- comment here -->