Small caps. You could guess it already from the name, small caps are small capitals. Capitals which have the same height as lowercase characters.

你可能看名字就猜出来了，小型大写就是小号的大写字母。和小写字母一样高度的大写字母。

Why are small caps needed? Because of several typographical reasons. First of all a whole word set in caps will look awful, it will drown out the rest of the text. Second, in lots of typefaces the capitals are not designed and spaced to work together, but to be followed by a lowercase character. Small caps however are designed to purely work together. They will give a more pleasurable, harmonized result.

为什么会需要小型大写？基于几个排印上的原因。首先，全部设置大写的单词看起来一塌糊涂，会让所有文本湮没其中，难以辨识。其次，大部分字体中的大写，根本就不是为大写连排而设计的，它们的大写字母间距是为后面跟随小写字母而设计的。小型大写才是专为大写连排而设计的。它们会得到更舒服和谐的效果。

Having said that small capitals are capitals on x-height, it's mostly not 100% true. To optically give them the same height, the small caps will have to be slightly bigger than lowercase characters of the same font (see drawing).

前面说小型大写是和小写字母一样x-高度的大写字母，其实是不太准确的。要得到和小写字母同样的视觉高度，同字体的小型大写就必须比小写字母稍微的更大一些。

英文原文