You asked me ‘Why are little letters called “lower case”?’
It’s one of those terms that are used these days without people questioning their origins (like ‘mileage’: young people brought up with kilometres don’t know about miles but still often talk of distance as mileage).
Back in the days before computerized photographic fonts or typefaces, words were assembled from pieces of metal, each with a letter (or ‘character’) raised on its surface back to front.
They were assembled in what was called a composing stick by a tradesman called a ‘compositor’. The capitals were kept in compartmented boxes arranged above the little letters, that’s why little letters are called lower case and capital letters are upper case. Some compartments are bigger than others because some letters are used more commonly than others. For example ‘e’ is the most common English character so a lot more space is allocated to ‘e’ than, say, ‘z’.
The compositor would pick the letters from their cases and make them into words. Thus if he wanted to make the word ‘print’ he would take each letter - which was back to front - and assemble, in the stick, ‘tnirp' which, when ink was rolled on to it, would come put as ‘print’ when pressed on to paper.
The clip on the right was springloaded so that, as the letters were loaded, it could be pushed up against them to hold them in place.