Somali officials were required to learn the orthography and attempts were made to inculcate mass literacy—in 1973 among urban and rural sedentary Somalis, and in 1974-75 among nomads. Although a few texts existed in the new script before 1973, in most cases new books were prepared presenting the government's perspective on Somali history and development. Somali scholars also succeeded in developing a vocabulary to deal with a range of subjects from mathematics and physics to administration and ideology. "The official language of the Republic of Somaliland is Somali, and the second language is Arabic."(art.6 of Constitution 2001) Religion Almost all Somalis are Sunni Muslims; Islam is the principal faith and state religion. Though traces of pre-Islamic traditional religion exist in Somaliland, Islam is extremely important to the Somali sense of national identity. Many of the Somali social norms come from their religion. For example, men shake hands only with men, and women shake hands with women. Many Somali women cover their heads and bodies with a hijab when they are in public. In addition, Somalis abstain from pork, gambling, and alcohol, and receiving or paying any form of interest. Muslims generally congregate on Friday afternoons for a sermon and group prayer. Accordance with these prohibitions depends on each individual's level of orthodoxy. Nevertheless there has been Catholic missionary activity. In colonial days, British Somaliland was under the care of the Vicariate Apostolic of Arabia, like the Vicariate Apostolic of the Gallas (including French Somaliland as well as its Ethiopian main territory) confided to the Order of Friars Minor Capuchin. Dress and custom of Somaliland Dress code The dress code in Somaliland encompasses traditional western and Islamic dress customs. However, most Somalis in this region prefer traditional Islamic dress code while a minority choose to both wear western-style clothing and cultural tradition. Men and women in Somaliland dress different, therefore they are categorised into two sections: Men in Somaliland wear trousers or a flowing sarong-like traditional kilt known as macawiis. Also, the majority wear shirts and embroided shawls. Due to Somaliland's Islamic heritage, some Somalis in this region wear long dresses known in the Arab and Islamic worlds as khameez. Somaliland's climate is mainly hot so many men wear an embroidered cap known as koofiyad. Recent years, many men in Somaliland choose to wear suits and ties to look more modern. This Western dress code is dominant amongst members of the