Do you ever wonder why some lowercase letters look nothing like their corresponding capitals? No? Well, people should wonder stuff like that more often.
Anyway, I'm going to tell you how the capital letters turned into the lowercase letters. It all started back in Ancient Rome when all they had were capitals (adapted from the Phoenician and Greek alphabets). The capitals were at their finest in 113 C.E. when the Emperor Trajan had them inscribed on a column in the Forum of Trajan (see the excellent writeup at Trajan's Column). These capitals have served as a model for those of all later Roman alphabets and some say no one has ever improved upon them.
But although the Trajan capitals were perfect for chiseling into stone, they were not well suited to writing quickly on less permanent media such as a stylus on a waxen tablet or a reed pen on papyrus. As the Roman scribes began to use these materials more and greater writing speed was demanded of them, they simplified the letters and rounded the corners off to eventually produce the uncials.
The uncials, deriving their name from the Latin word "uncialis" meaning in this case "an inch high", though perhaps also infulenced by "uncus" meaning "crooked" or "hook-shaped", were an alphabet used from the 4th through the 18th centuries with some characteristics of capitals and some of lowercase. They further developed into the half-uncials or "semiuncials" which were even closer to our modern-day lowecase alphabet. (The Book of Kells is written in half-uncials.)
Only one more step was needed to get to the lowercase alphabet as we know it. The uncials and half-uncials were not used as small letters: a sentence written in uncials did not start with a capital, but with just another uncial. The first to institute the convention of starting a sentence with a capital letter, as well as develop the half-uncials into the beautiful Carolingian minuscule, was Alcuin of York when he was working for Charlemagne at Tours, in the late 700s.
There were still some changes in store for the alphabet, such as the Gothic letters or the invention of printing, but by about 900 they were immediately recognizable as the same alphabet we use today.
Check out my awesome ascii art of the evolution of the letter A:
A A aa
A A A A a a a-a-a-a
A A A A _a a a
A-A-A-A A A a' a _.a-a-a
A A A _A' A a' a a _a
A A A _A' A a' a a a a a a
A A AA' A a-a' aa `-a-a' a
The first is a Roman Capital, the second is just an alternate form of the capital, the third is an uncial, and the fourth is a modern lowercase letter. Can you see how the crossbar and the left leg fused together into a single loop? Similar changes took place with the other letters:
- B lost its top loop,
- D extended and rotated its upper serif,
- E got rounded and grew a connecting stroke between the top two horizontal lines,
- G's hook extended down below the letter and then the main part closed into a circle,
- H lost the top half of its right vertical line,
- I and J got dots,
- L's horizontal line shrunk until it disappeared,
- N got very rounded,
- Q's tail grew,
- R combined its loop and leg into one stroke which then got detached from the vertical line and shrunk,
- T's bar dropped,
and the other letters have no significant difference between their capital and lowercase versions.