Getting Easy Access to International Key Characters

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new: 2016 and some things have changed and some things haven't - take a look at: Windows 10 doesn't make it straightforward to use international characters but.... 

Many English-language users have need for easy access to accented and other non-English characters. While this can be done by learning a small number of Alt+0xxx kecode combinations, or using the Windows Charmap accessory, many Windows users may find it useful to install and learn to use the Windows US International Keyboard setup.

Install the United States (International) keyboard

Open Control Panel, and go to the Keyboard icon. Click on theLanguage tab. Double-click on the English (United States) item (or, with that item selected, click on the Properties button). From the drop-down list, choose United States- International. Click OK.

(You may need to have your Windows CD handy as some files will be installed).

Using the International keyboard

At first glance, your keyboard will seem normal. However, you may notice that several keys don't seem to do anything... however, if you press one of those keys followed by some letters, interesting things happen:

• Circumflex (the ^ character)... with the International keyboard, holding down shift+6 (which gives the circumflex), followed by the letters a or e produces that vowel with a circumflex.
• Accent Grave is produced by typing the single quotation mark ( ' ) followed by a letter a, e etc... the result is an accented vowel.
• Tilde--this key (usually next to the number 1-- note you need to hold down shift) followed by an a or an n produces that character with a tilde on top.
• Acute Accent is produced using the apostrophe (the unshifted character underneath the tilde-- not the single quotation mark) followed by an a, e, or i.
• Umlaut:use the double quotation mark ( " ) followed by an a, e, i, etc. to produce those two little dots over the letter. (Thanks to Adrienee Mahafey for telling me the name of the two dots, also known as a "diaeresis").

Note that you will only get the special character if you type the key combination for a letter which can use one of those characters... if you type a contraction like isn't for example, you won't end up with an accent grave over the letter t.

But what if you actually want to get the character on the key-- single or double quotation marks, for example? To do so, press the key followed by the space bar. This can be a bit of a pain when putting a phrase in quotes.

Another way...

Alternatively, holding down the right-Alt key on your keyboard or Ctrl + Alt at the same time, along with many of the letters of the keyboard, and you will get an alternative (often accented) character as shown in the following illustration. (Illustration scanned from Windows 95 Secrets by Brian Livingston and David Straub (1995, IDG Books, p. 501)
A useful page on entering Accents and International Key Characters in both Mac and Windows can be found at: http://lrcnt.fas.harvard.edu/Resources/Documentation/accents.htm

Comment (July 2011): The release of Apple's Mac OSX 10.7 Lion makes it easy to add international characters on the Mac. (See this article). It notes:

"Windows is messy and inconsistent when you want to enter accented characters. "You can choose the United States-International" keyboard layout in the Keyboard applet in the Windows Control Panel, which enables you (for example) to press the quotation mark key, then an "u" to get an u-umlaut. Of course, this is different from the method built into Microsoft Word (with any keyboard), in which you press Ctrl-double quotation mark, then "u" to get u-umlaut. The best system for inserting accented characters in Windows is the open-source AllChars program, available from http://sourceforge.net/projects/allchars/, which uses the right Ctrl-key, followed by an intuitive pair of characters, to create accented characters system-wide. Or you could just buy a Mac."