In the Western world, society expects alphabets to be the written form of communication, even outside the realm of the Latin alphabet. Notable alphabets also include the Cyrillic, Green, Georgian, and Armenian alphabets, and other alphabets that may exist typically exist for a significantly smaller portion of the global population. In an alphabet, the letters can represent vowels or consonants, but never both, and both are required features. In an abjad, as is the case with Arabic or Hebrew, consonants are the base, and vowels are an optional secondary feature of the system. Being written from right to left is not technically a requirement for a writing system to be an abjad, though the vast majority of abjad uses are in that direction. And finally, an abugida system contains characters of either all vowels or consonants plus vowels, but never consonants alone. The accents may exist to change the vowel, consonant, or other portions of the character pronunciation, though not necessarily in every possible case.
