Special insertions
LaTeX provides commands for inserting characters that have a special meaning do not correspond to simple characters you can type.

Reserved characters
The following characters play a special role in LaTeX and are called “reserved characters” or “special characters”.

# $ % & ~ _ ^ \ { }

Whenever you write one of these characters into your file, LaTeX will do something special. If you simply want the character to be printed as itself, include a \ in front of the character. For example, \$ will produce $ in your output.
One exception to this rule is \ itself, because \\ has its own special (context-dependent) meaning. A roman \ is produced by typing $\backslash$ in your file, and a typewriter \ is produced by using ‘\’ in a verbatim command (see verbatim).
Also, \~ and \^ place tilde and circumflex accents over the following letter, as in õ and ô (see Accents); to get a standalone ~ or ^, you can again use a verbatim command.
Finally, you can access any character of the current font once you know its number by using the \symbol command. For example, the visible space character used in the \verb* command has the code decimal 32, so it can be typed as \symbol{32}.
You can also specify octal numbers with ' or hexadecimal numbers with ", so the previous example could also be written as \symbol{'40} or \symbol{"20}.

Text symbols
LaTeX provides commands to generate a number of non-letter symbols in running text. Some of these, especially the more obscure ones, are not available in OT1; you may need to load the textcomp package.
\copyright 	\textcopyright 	 The copyright symbol, ©.
\dag 	 The dagger symbol (in text).
\ddag 	 The double dagger symbol (in text).
\LaTeX 	 The LaTeX logo.
\LaTeXe 	 The LaTeX2e logo.
\guillemotleft («) 	\guillemotright (») 	\guilsinglleft (‹) 	\guilsinglright (›) 	 Double and single angle quotation marks, commonly used in French: «, », ‹, ›.
\ldots 	\dots 	\textellipsis 	 An ellipsis (three dots at the baseline): ‘…’. \ldots and \dots also work in math mode.
\lq 	 Left (opening) quote: ‘.
\P 	\textparagraph 	 Paragraph sign (pilcrow).
\pounds 	\textsterling 	 English pounds sterling: £.
\quotedblbase („) 	\quotesinglbase (‚) 	 Double and single quotation marks on the baseline: „ and ‚.
\rq 	 Right (closing) quote: ’.
\S 	 Section symbol.
\TeX 	 The TeX logo.
\textasciicircum 	 ASCII circumflex: ^.
\textasciitilde 	 ASCII tilde: ~.
\textasteriskcentered 	 Centered asterisk: *.
\textbackslash 	 Backslash: \.
\textbar 	 Vertical bar: |.
\textbardbl 	 Double vertical bar.
\textbigcircle 	 Big circle symbol.
\textbraceleft 	 Left brace: {.
\textbraceright 	 Right brace: }.
\textbullet 	 Bullet: •.
\textcircled{letter} 	 letter in a circle, as in ®.
\textcompwordmark 	\textcapitalwordmark 	\textascenderwordmark 	 Composite word mark (invisible). The \textcapital... form has the cap height of the font, while the \textascender... form has the ascender height.
\textdagger 	 Dagger: \dag.
\textdaggerdbl 	 Double dagger: \ddag.
\textdollar (or $) 	 Dollar sign: $.
\textemdash (or ---) 	 Em-dash: — (for punctuation).
\textendash (or --) 	 En-dash: – (for ranges).
\texteuro 	 The Euro symbol: €.
\textexclamdown (or !`) 	 Upside down exclamation point: ¡.
\textgreater 	 Greater than: >.
\textless 	 Less than: <.
\textleftarrow 	 Left arrow.
\textordfeminine 	\textordmasculine 	 Feminine and masculine ordinal symbols: ª, º.
\textperiodcentered 	 Centered period: \cdot.
\textquestiondown (or ?`) 	 Upside down question mark: ¿.
\textquotedblleft (or ``) 	 Double left quote: “.
\textquotedblright (or ') 	 Double right quote: ”.
\textquoteleft (or `) 	 Single left quote: ‘.
\textquoteright (or ') 	 Single right quote: ’.
\textquotestraightbase 	\textquotestraightdblbase 	 Single and double straight quotes on the baseline.
\textregistered 	 Registered symbol: ®.
\textrightarrow 	 Right arrow.
\textthreequartersemdash 	 “Three-quarters” em-dash, between en-dash and em-dash.
\texttrademark 	 Trademark symbol: ^{\hbox{TM}}.
\texttwelveudash 	 “Two-thirds” em-dash, between en-dash and em-dash.
\textunderscore 	 Underscore: _.
\textvisiblespace 	 Visible space symbol.

Accents
LaTeX has wide support for many of the world’s scripts and languages, through the babel package and related support. This section does not attempt to cover all that support. It merely lists the core LaTeX commands for creating accented characters.
The \capital... commands produce alternative forms for use with capital letters. These are not available with OT1.
\" 	\capitaldieresis 	 Produces an umlaut (dieresis), as in ö.
\' 	\capitalacute 	 Produces an acute accent, as in ó. In the tabbing environment, pushes current column to the right of the previous column (see tabbing).
\. 	 Produces a dot accent over the following, as in ȯ.
\= 	\capitalmacron 	 Produces a macron (overbar) accent over the following, as in ō.
\^ 	\capitalcircumflex 	 Produces a circumflex (hat) accent over the following, as in ô.
\` 	\capitalgrave 	 Produces a grave accent over the following, as in ò. In the tabbing environment, move following text to the right margin (see tabbing).
\~ 	\capitaltilde 	 Produces a tilde accent over the following, as in ñ.
\b 	 Produces a bar accent under the following, as in o_. See also \underbar hereinafter.
\c 	\capitalcedilla 	 Produces a cedilla accent under the following, as in ç.
\d 	\capitaldotaccent 	 Produces a dot accent under the following, as in ọ.
\H 	\capitalhungarumlaut 	 Produces a long Hungarian umlaut accent over the following, as in ő.
\i 	 Produces a dotless i, as in ‘i’.
\j 	 Produces a dotless j, as in ‘j’.
\k 	\capitalogonek 	 Produces a letter with ogonek, as in ‘ǫ’. Not available in the OT1 encoding.
\r 	\capitalring 	 Produces a ring accent, as in ‘o*’.
\t 	\capitaltie 	\newtie 	\capitalnewtie 	 Produces a tie-after accent, as in ‘oo[’. The \newtie form is centered in its box.
\u 	\capitalbreve 	 Produces a breve accent, as in ‘ŏ’.
\underbar 	 Not exactly an accent, this produces a bar under the argument text. The argument is always processed in horizontal mode. The bar is always a fixed position under the baseline, thus crossing through descenders. See also \underline in Math miscellany. See also \b above.
\v 	\capitalcaron 	 Produces a háček (check, caron) accent, as in ‘ǒ’.

Non-English characters
Here are the basic LaTeX commands for inserting characters commonly used in languages other than English.
\aa 	\AA 	 å and Å.
\ae 	\AE 	 æ and Æ.
\dh 	\DH 	 Icelandic letter eth: ð and Ð.
\dj 	\DJ 	 Crossed d and D, a.k.a. capital and small letter d with stroke.
\ij 	\IJ 	 ij and IJ (except somewhat closer together than appears here).
\l 	\L 	 ł and Ł.
\ng 	\NG 	 Latin letter eng, also used in phonetics.
\o 	\O 	 ø and Ø.
\oe 	\OE 	 œ and Œ.
\ss 	\SS 	 ß and SS.
\th 	\TH 	 Icelandic letter thorn: þ and Þ.

\rule
Synopsis:

\rule[raise]{width}{thickness}

The \rule command produces rules, that is, lines or rectangles. The arguments are:
raise 	How high to raise the rule (optional).
width 	The length of the rule (mandatory).
thickness 	The thickness of the rule (mandatory).

\today
The \today command produces today’s date, in the format ‘month dd, yyyy’; for example, ‘July 4, 1976’. It uses the predefined counters \day, \month, and \year (see \day \month \year) to do this. It is not updated as the program runs.
The datetime package, among others, can produce a wide variety of other date formats.