Abugida in the context of "Ge'ez script"

A writing system comprises a set of symbols, called a script, as well as the rules by which the script represents a particular language. The earliest writing appeared during the late 4th millennium BC. Throughout history, each independently invented writing system gradually emerged from a system of proto-writing, where a small number of ideographs were used in a manner incapable of fully encoding language, and thus lacking the ability to express a broad range of ideas.

Writing systems are generally classified according to how their symbols, called graphemes, relate to units of language. Phonetic writing systems – which include alphabets and syllabaries – use graphemes that correspond to sounds in the corresponding spoken language. Alphabets use graphemes called letters that generally correspond to spoken phonemes. They are typically divided into three sub-types: Pure alphabets use letters to represent both consonant and vowel sounds, abjads generally only use letters representing consonant sounds, and abugidas use letters representing consonant–vowel pairs. Syllabaries use graphemes called syllabograms that represent entire syllables or moras. By contrast, logographic (or morphographic) writing systems use graphemes that represent the units of meaning in a language, such as its words or morphemes. Alphabets typically use fewer than 100 distinct symbols, while syllabaries and logographies may use hundreds or thousands, respectively.

Devanagari (/ˌdeɪvəˈnɑːɡəri/ DAY-və-NAH-gə-ree; in script: देवनागरी, IAST: Devanāgarī, Sanskrit pronunciation: [deːʋɐˈnaːɡɐriː]) is an Indic script used in the Indian subcontinent. It is a left-to-right abugida (a type of segmental writing system), based on the ancient Brāhmī script. It is one of the official scripts of India and Nepal. It was developed in, and was in regular use by, the 8th century CE. It had achieved its modern form by 1000 CE. The Devanāgarī script, composed of 48 primary characters, including 14 vowels and 34 consonants, is the fourth most widely adopted writing system in the world, being used for over 120 languages, the most popular of which is Hindi (हिन्दी).

The orthography of this script reflects the pronunciation of the language. Unlike the Latin alphabet, the script has no concept of letter case, meaning the script is a unicameral alphabet. It is written from left to right, has a strong preference for symmetrical, rounded shapes within squared outlines, and is recognisable by a horizontal line, known as a शिरोरेखा śirorekhā, that runs along the top of full letters. In a cursory look, the Devanāgarī script appears different from other Indic scripts, such as Bengali-Assamese or Gurmukhi, but a closer examination reveals they are very similar, except for angles and structural emphasis.

The Brahmic scripts, also known as Indic scripts, are a family of abugida writing systems. They are descended from the Brahmi script of ancient India and are used by various languages in several language families in South, East and Southeast Asia: Indo-Aryan, Dravidian, Tibeto-Burman, Mongolic, Austroasiatic, Austronesian, and Tai. They were also the source of the dictionary order (gojūon) of Japanese kana.

Brahmi (/ˈbrɑːmi/ BRAH-mee; 𑀩𑁆𑀭𑀸𑀳𑁆𑀫𑀻; ISO: Brāhmī) is a writing system from ancient India that appeared as a fully developed script in the 3rd century BCE. Its descendants, the Brahmic scripts, continue to be used today across South and Southeastern Asia.

Brahmi is an abugida and uses a system of diacritical marks to associate vowels with consonant symbols. The writing system only went through relatively minor evolutionary changes from the Mauryan period (3rd century BCE) down to the early Gupta period (4th century CE), and it is thought that as late as the 4th century CE, a literate person could still read and understand Mauryan inscriptions. Sometime thereafter, the ability to read the original Brahmi script was lost. The earliest (indisputably dated) and best-known Brahmi inscriptions are the rock-cut edicts of Ashoka in north-central India, dating to 250–232 BCE. During the late 20th century CE, the notion that Brahmi originated before the 3rd century BCE gained strength when archaeologists working at Anuradhapura in Sri Lanka retrieved Brahmi inscriptions on pottery belonging to the 450-350 BCE period.

Writing systems are used to record human language, and may be classified according to certain common features.

Gurmukhī (Punjabi: ਗੁਰਮੁਖੀ [ˈɡʊɾᵊmʊkʰiː], Shahmukhi: گُرمُکھی) is an abugida developed from the Laṇḍā scripts, standardized and used by the second Sikh guru, Guru Angad (1504–1552). Commonly regarded as a Sikh script, Gurmukhi is used in Punjab, India as the official script of the Punjabi language.

The primary scripture of Sikhism, the Guru Granth Sahib, is written in Gurmukhī, in various dialects and languages often subsumed under the generic title Sant Bhasha or "saint language", in addition to other languages like Persian and various phases of Indo-Aryan languages.