Today I found a table describing the keystrokes you can use to generate different letters in another language than the bare ASCII set used in the US. For example, it is nice to use "à" in French whenever necessary because "à" (a preposition) has nothing to do with "a" (a conjugated verb).

Microsoft includes that feature for most of their software. It may not work in all software, although you can always open wordpad and then copy and paste the output. (Notepad is not enough, it does not support UTF-8 or Unicode too well.)

The Ctrl or Ctrl + Shift used to enter the dead key must be released before hitting the letter that is to receive the diacritic. Use the Shift key to create the uppercase version of the letter.