The Semitic languages are a branch of the Afroasiatic language family originating in the Middle East.
 Semitic languages are spoken by more than 330 million people across much of Western Asia, North Africa and the Horn of Africa, as well as in often large expatriate communities in North America and Europe, with smaller communities in the Caucasus and Central Asia.
 The terminology was first used in the 1780s by members of the Göttingen School of History, who derived the name from Shem, one of the three sons of Noah in the Book of Genesis.
The Tigrinyas (also referred to as Biher Tigrinya, Kebessa, and Biher-Tigrinya) are an ethnic group inhabiting central Eritrea, an area spanning the Southern and Central, as well as the Northern Red Sea and Anseba Regions - mostly part of the Eritrean highlands (hence the name Kebessa meaning 'highland' in the local language).
 Ethnolinguistically, Tigrinyas are related to the Tigrayans of Ethiopia, both of whom speak Tigrinya, an Ethiopian Semitic language belonging to the Afroasiatic family.
 Most are followers of the Eritrean Orthodox Tewahedo Church.
 They make up roughly 55% of Eritrea's population numbering 3.4 million people.
 They are not to be confused with the Tigre people who speak Tigre, a closely related Afroasiatic language.
Hebrew ( ; , "Ivrit " ] or ] ) is a Northwest Semitic language native to Israel, spoken by over 9 million people worldwide.
 Historically, it is regarded as the language of the Israelites and their ancestors, although the language was not referred to by the name Hebrew in the Tanakh.
 The earliest examples of written Paleo-Hebrew date from the 10th century BCE.
 Hebrew belongs to the West Semitic branch of the Afroasiatic language family.
 Hebrew is the only living Canaanite language left, and the only truly successful example of a revived dead language.
Highland East Cushitic, or Sidamic, is a branch of the Afroasiatic language family spoken in south-central Ethiopia.
 They are often grouped with Lowland East Cushitic, Dullay, and Yaaku as "East Cushitic", but that group is not well defined and considered dubious.
Hausa ( ) ("Yaren Hausa" or "Harshen Hausa") is the Chadic language (a branch of the Afroasiatic language family) with the largest number of speakers, spoken as a first language by more than 70 million people, and as a second language by another 40 to 50 million or more.
 Originally the language of the Hausa people stretching across southern Niger and northern Nigeria, it has developed into a lingua franca across much of western Africa for purposes of trade.
 In the 20th and 21st centuries, it has become more commonly published in print and online.
Hozo is an Afroasiatic language spoken mostly in the Kondala woreda of Mirab Welega Zone (Western Oromia) by peoples generically known as "Mao".
 There are smaller groups of Hozo speakers in Mana Sibu woreda.
 The term Hozo is usually understood by the Mao to refer to a clan.
 Hozo speakers prefer to call themselves Amo.
 Hozo and Seze are sometimes called Begi Mao.
 Hozo is spoken by roughly 3,000 people in Ethiopia.
 Hozo is also a clan in the Begi area.
 The Hozo language is also known as Begi-Mao and Mao of Begi.
 Its classification is Afro-Asiatic, Omotic, and Mao.
 The word Mao is Omotic and means ‘man; people’, occurring as [ma:ɪ] in Seze and as [mɔ:] in Hozo.
 Mao is frequently used as an ethnic term.
 There is a kind of Mao identity across language differences in Ethiopia.
 While it is generally accepted today that Omotic is one of the primary branches of the Afro-Asiatic family, the position of the four languages Hozo, Seze, Ganza and Northern Mao is still being discussed.
 The Mao languages are the least documented within Omotic, and Omotic itself is the least documented of the Afroasiatic groups.
The Chadic languages are a branch of the Afroasiatic language family that is spoken in parts of the Sahel.
 They include 150 languages spoken across northern Nigeria, southern Niger, southern Chad, Central African Republic and northern Cameroon.
 The most widely spoken Chadic language is Hausa, a lingua franca of much of inland West Africa.
Meem is the letter Mem (also known as Meem / Mim), the thirteenth letter of many Semitic language abjads, including Phoenician, Aramaic, Hebrew and Arabic
The Cushitic languages are a branch of the Afroasiatic language family.
 They are spoken primarily in the Horn of Africa (Somalia, Eritrea, Djibouti, and Ethiopia), as well as the Nile Valley (Sudan and Egypt), and parts of the African Great Lakes region (Tanzania and Kenya).
The Proto–Afroasiatic language is the reconstructed proto-language from which all modern Afroasiatic languages are descended.
 It is believed by scholars to have been spoken as a single language around 12,000 to 18,000 years ago, but there is no consensus as to where the Afroasiatic Urheimat, the homeland of Proto-Afroasiatic speakers, was located.
 Although Afroasiatic is the earliest attested language family in the world, the reconstruction of Proto-Afroasiatic is problematic and largely lacking, which is sometimes attributed to the sheer age of the language.
 Reconstructed words for fauna and flora and evidence of linguistic contact with language families known to have been spoken in Eurasia suggest that its home was in the Middle East, probably the Levant.
 Evidence of Cushitic, formerly spoken in the south of Arabia, also speaks for a Middle Eastern origin, but some proposals also claim Northern Africa or the Horn of Africa.

Question: What is a branch of the Afroasiatic language family and also known as the letter Mem?
Answer: Semitic