I believe \backslash may be used in math formulae, but not into text itself. Lamport's, Kopka's, and Mittelbach's texts have said as much (but no more), and so left me hanging on how to get a backslash into regular text.
Thanks!
Edit: added question for tilde.
Well if that isn't annoying:
Thank for reading. :)
Edit: added code for tilde.
The Comprehensive LaTeX Symbol List is your friend. \textbackslash and \textasciitilde are found in Table 2 of the list, and page 101 has some other options for the tilde ($\sim$ and \texttildelow from the textcomp package, possibly using some font other than Computer Modern to get a nice vertically centered tilde), and a suggestion to use the url package if you are typesetting URLs or Unix file names.
You can also use the "plain TeX" method of indexing the actual ascii character in the current font:
\char`\\
\char`\~
I often use the former for writing macros that need the backslash in the typewriter font; \textbackslash will sometimes still use the roman font depending on the font setup. Of course, if you're using these a lot you should define your own macro for them:
\newcommand\SLASH{\char`\\}
Hmm; \textbackslash (mentioned by others) isn't in my reference book (Helmut and Kopka).
At any rate, math mode provides \sim, \backslash, and \setminus (the latter two appear to look the same).
My LaTeX book – which, as you would expect, features the \ extensively – seems to use the verbatim environment. For example, this code:
\begin{verbatim}
\addtocounter{footnote}{-1}\footnotetext{Small insects}
\stepcounter{footnote}\footnoteext{Large mammals}
\end{verbatim}
Produces this text in the book:
\addtocounter{footnote}{-1}\footnotetext{Small insects}
\stepcounter{footnote}\footnoteext{Large mammals}
The \verb command is similar, but the argument must be on one line only. The first character after the b is the delimiter; for example:
\verb=\emph{stuff}=
will produce
\emph{stuff}
So you could presumably get your backslash by typing:
\verb=\=
You can also add a * – i.e. \verb* or \begin{verbatim*} – to make whitespace visible.
It is interesting to speculate how you would get an example of a verbatim environment into a document.. (using \verb to do the last line, I guess)
For the tilde, you can use empty curly brace pair. That puts the "over the letter" tilde over an "empty" letter, so it's placed upward.
My tilde\~{}here
I occurs to me that you might be trying to type URLs. In that case, the url package takes care of everything for you:
\usepackage{url}
...
\url{somewhere\home\~will}
Thank you Will, I was trying to typeset teletype backslash (thick one) in new command. I've found way how to solve it but using url package is much more elegant.
I was trying to put a tilde into a website using
\url{http://somewhere.com/~myusername/}
but adobe reader would automatically make a link that would be broken because it would use the wrong tilde character. I ended up using
\usepackage{textcomp}
...
\texttt{http://somewhere.com/{\texttildelow}myusername/}
That did the trick for what I was doing. Of course if one wanted to make an actual link then one would use the hyperref package.
textcomp’s \texttildelow is actually quite a bad choice: it’s too low for most fonts.
A much better rendering can be achieved by the following, which tweaks the appearance of the (otherwise too wide) $\sim$:
{\raise.17ex\hbox{$\scriptstyle\sim$}}
This was taken from the Arbitrary LateX reference … the page also provides a good comparison sheet:
When used in \texttt, I would add a \mathtt around the tilde, to make it fit the font better:
{\raise.17ex\hbox{$\scriptstyle\mathtt{\sim}$}}
The difference is small but noticeable.