Sometimes you just want a character that is not a standard letter, that will show up in email or a webpage. For example, we made this handy 'Used Car Buying Checklist' without any HTML forms by simply using the Unicode character for a checkbox.
? ? ?
☐ ☑ ☒
The standardized Unicode characters that best represent a checkbox are:
?, U+2610 Ballot box
?, U+2611 Ballot box with check
?, U+2612 Ballot box with X
If you don't have a Unicode-safe editor you can naturally spell them as ☐ ☑ and ☒.