Or little letters and big letters!

You probably already know (and this snippet of information is known as a 'swan's wing', but that's another story) that the terms upper case and lower case derive from the good old days of metal type when typesetting was literally constructed manually, one letter at the time, into a 'block' and all the individual pieces were kept in two trays - the 'upper' case or capitals were (strangely) the upper of the two trays and the 'lower' case, or little letters, were (you've got it) the lower of the two trays.

And once the printing was complete all the thousands of bits of type would be bashed out into a bigger tray and a young apprentice would have to put them back into the correct compartments in the two trays (which would take forever!) and this poor soul was known as The Printer's Devil - and there's many a pub named after him.

Famous Printer's Devils were Benjamin Franklin, Thomas Jefferson, Walt Whitman and Mark Twain.

Generally speaking, almost all text is made up of lower case type with capitals being used only at the beginning of sentences and for proper nouns and although ALL CAPS are often used for headlines you do occasionally see larger pieces of body copy produced totally in capitals - and usually it's almost unreadable!