On the Case
Q. Are capital letters and uppercase letters the same thing?
A. Yes, they are synonyms. Once upon a time, they were referred to as majuscules, from a Latin word meaning larger, while lowercase letters were called minuscules, from a Latin word meaning smaller. Capital meant principal in Middle English.
I find the origin of the terms uppercase and lowercase fascinating. In the early days of printing, the compositor sat at a bench in front of two cases filled with individually crafted letters. He would pull them out letter by letter, selecting the small letters from the lower (and closer) case, and the less frequently used capital letters from the upper case.
Sidebar: capitalization rules
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