An alphabet is a writing system, a list of symbols for writing. The basic symbols in an alphabet are called letters. In an alphabet, each letter is a symbol for a sound or related sounds. To make the alphabet work better, more signs assist the reader: punctuation marks, spaces, standard reading direction, and so on.

The name alphabet comes from Aleph and Beth, the first two letters in the Phoenician alphabet.

This article is written with the Roman alphabet (or Latin alphabet).  It was first used in Ancient Rome to write Latin.  Many languages use the Latin alphabet: it is the most used alphabet today.[1]

It seems that the idea of an alphabet – a script based entirely upon sound – has been copied and adapted to suit many different languages. Although no alphabet fits its language perfectly, they are flexible enough to fit any language approximately. The alphabet was a unique invention.[2]p12

The Roman alphabet, the Cyrillic, and a few others come from the ancient Greek alphabet, which dates back to about 1100 to 800BC.[3]p167 The Greek alphabet was probably developed from the Phoenician script, which appeared somewhat earlier, and had some similar letter-shapes.

The Phoenicians spoke a Semitic language, usually called Canaanite. The Semitic group of languages includes Arabic, Maltese, Hebrew and also Aramaic, the language spoken by Jesus. We do not know much about how the alphabetic idea arose, but the Phoenicians, a trading people, came up with letters which were adapted by the early Greeks to produce their alphabet. The one big difference is that the Phoenician script had no pure vowels. Arabic script has vowels which may, or may not, be shown by diacritics (small marks above or below the line).[4] The oldest Qu'ran manuscripts had no diacritics.[5] Israeli children to about the third grade use Hebrew texts with vowel 'dots' added.[6]p89

No ancient script, alphabetic or not, had pure vowels before the Greeks. The Greek alphabet even has two vowels (Eta) and Epsilon) for 'e' and two (Omega and Omicron) for 'o', to distinguish between the long and short sounds.[7] It appears that careful thought went into both the Phoenician invention and the Greek adaptation, but no details survive of either process.[8]

Semitic scripts apparently derive from Proto-Sinaitic, a script of which only 31 inscriptions (plus 17 doubtful) are known. It is thought by some researchers that the original source of this script was the Egyptian hieratic script, which by the late Middle Kingdom (about 1900BC) had added some alphabetic signs for representing the consonants of foreign names. Egyptian activity in Sinai was at its height at that time.[9] A similar idea had been suggested many years previously.[10]

A list of alphabets and examples of the languages they are used for:

Other writing systems do not use letters, but they do (at least in part) represent sounds. For example, many systems represent syllables. In the past such writing systems were used by many cultures, but today they are almost only used by languages people speak in Asia.  A syllabary is a system of writing that is similar to an alphabet. A syllabary uses one symbol to indicate each syllable of a word, instead of one symbol for each letter of the word. For example, a syllabary would use one symbol to mean the syllable "ga", instead of two letters of the alphabet "g" and "a".

Originally, 1200 BC in the Shang dynasty, Chinese characters were mainly "pictographic", using pictures to show words or ideas.  Now only 1% of Chinese characters are pictographic.[11]p97 97% of modern characters are SP characters.  These are a pair of symbols, one for meaning (semantics) and the other for pronunciation.[11]p99 In many cases the P and S parts are put together into one joint character.[12]  Chinese is not one spoken language, but many, but the same writing system is used for all.  This writing system has been reformed a number of times.