AS EVEN THE SMALLEST school-age child knows, the alphabet is the series of letters used in writing a language. The word alphabet comes from alpha and beta, the first two letters of the Greek alphabet.

The Romans did not invent the 26-letter alphabet that we use today. They simply perfected a system that had been growing for thousands of years.In ancient times, people could only communicate with one another by speaking or by making gestures. They had no way to keep records of important events, unless they memorized the story of a great battle or important happening. They had no way to send messages over long distances unless they passed them from one person to the next by word of mouth, or had one person memorize the passage and then deliver it.

Simple writing evolved when people learned to draw pictures to express their ideas. In ideography, each picture conveyed an idea. Ideography enabled even people who did not speak the same language to communicate with each other. Then people learned logography, expressing ideas indirectly by using signs to stand for words of an idea. For example, instead of drawing pictures of four goats, a person could draw one sign for the number "4", and one for "goats." The syllabic system used a sign representing one word that could be used not only for that word, but for any phonetic combination that sounded like that word. Finally, people developed alphabets in which individual signs stood for particular sounds.

In historical order, the Egyptians used a system of several hundred signs that stood for full words or for syllables. These signs stood for consonants in syllables, but not for the vowels. Egyptian writing developed around 3000 B.C. and was formally a picture writing, and structurally a word and syllabic writing.

The Semites, who lived in Syria and Palestine, worked out their own set of characters to stand for the consonants in their language in 1500 B.C. Like the Egyptians, they used signs to show the consonants of syllables. The oldest Semitic alphabet comes from the Sinai peninsula.

The Phoenicians, who lived along the coast of the Mediterranean Sea, developed a system of 22 signs about 1000 B.C. Structurally, their alphabet was related to the Egyptian and Semitic, with signs for consonant sounds. However, historians find it difficult to trace the formal relations between Semitic and Phoenician signs, because Phoenician has both pictographic and diagrammatic signs, and because so little is known of the ancient systems used in Syria or Palestine.

The Cypriots, of the island of Cyprus, developed an alphabet of their own. With an unknown word-syllable system, they worked out an alphabet of 56 signs, each standing for an initial consonant and a different vowel.

The Greeks were the first to evolve a system of vowel signs, creating the first alphabetic system of writing. They took over the Phoenician names for their signs, and in most cases the signs themselves. The Phoenician alphabet included more consonants than the Greeks needed in their language, so they used the extra signs for vowel sounds. They improved on both Phoenician and Cypriot ideas, because they could combine individual letters for both consonants and vowels to spell any word they wanted.

The Etruscans carried the Greek alphabet with them when they moved to central Italy from somewhere in the eastern Mediterranean region sometime after 1000 B.C. The Romans learned the alphabet from the Etruscans and gave it much the same form we use today. The early Roman alphabet had about 20 letters, and gradually gained 3 more.

Capital letters were the only forms used for hundreds of years. Many experts consider the Roman alphabet to have been perfected by A.D. 114. That year, sculptors carved the inscriptions on a memorial column built to honor the emperor Trajan. The style of lettering they used is considered one of the most beautiful in the world.

Small letters gradually evolved from capitals. Scribes who copied books often used uncials, rounded letters, that were easier to form than some capitals. True lower-case letters developed later, when scribes saved space in books by using the smaller letters.

The alphabet today does not fit writing words in the English language. It does not have a separate character for every distinctive sound in English, and it has several characters with more than one sound. Many other languages written with Roman letters use accent marks to show changes in sound. Linguists use an almost perfect alphabet, the International Phonetic Alphabet, that has more than 80 characters.