An abugida (from Ge'ez አቡጊዳ ’äbugida), and likewise an alphasyllabary, is a segmental writing system in which consonant–vowel sequences are written as a unit: each unit is based on a consonant letter, and vowel notation is secondary. This contrasts with a full alphabet, in which vowels have status equal to consonants, and with an abjad, in which vowel marking is absent or optional. (In less formal contexts, all three types of script may be termed alphabets.) The terms also contrast them with a syllabary, in which the symbols cannot be split into separate consonants and vowels. Abugidas include the extensive Brahmic family of scripts of South and Southeast Asia.