According to the Constitution of August 17, 1945, Indonesia is a presidential republic. The President of the Republic, who holds office for 5 years and is elected by direct suffrage, is head of state and head of government and exercises executive power with the help of the Council of Ministers, responsible for him. Legislative power rests with the House of Representatives (made up of 500 members with a five-year mandate), flanked by a Chamber / council of regional representatives (also elected with a five-year mandate). An important organ of the state is also the People’s Consultative Congress, which traces the lines of political action and appoints the president and is made up of members of the two chambers and other military representatives appointed by the government or expression of some economic groups in the country. As for the administration of justice, the system in use in the country is based on Dutch law with local influences. The organization of the system provides for different levels of judgment: the District Court, the High Court and the Supreme Court. There are also some religious tribunals which deliberate on matters pertaining to the religious and family sphere. The death penalty is in effect. The country’s armed forces (army, air force, navy) were unified in 1966 and placed under the control of the Ministry of Defense. Military service is compulsory and lasts two years; there is also the possibility of a voluntary stop.
According to educationvv, the educational system, as well as the cultural one, has been particularly affected by European influences: from the 12th century onwards. XVII to XIX the General East India Company imposed a Protestant education in the country, with the help of Dutch teachers. Until independence, the entire school system, especially for secondary and higher education, therefore remained organized on the basis of the Dutch model. Subsequently the government took care to give the country a national school organization, imposing the compulsory teaching of up to 13 years (1954), extended to 16 years in 1993. Elementary education currently lasts 6 years, to from 7 years of age. Secondary education also lasts 6 years and includes 2 three-year cycles. Higher education is given in universities and some institutes. The main universities include, among others: Universitas Pakuan in Bogor, Universitas Padjadjaran in Bandung, Diponegoro University in Semarang, Technological Institutes and Polytechnic of Surabaya, Universitas Pelita Harapan in Tangerang, University of Indonesia in Depok and the faculties of Kalbar, Lampung and Riau. The percentage of illiteracy in the country was 8% in 2006.
The hydrographic network is very rich, although the development of individual watercourses is relatively limited due to the complex morphology and island fragmentation. In fact, only in Sumatra and in Borneo there are rivers of considerable length; however, all Indonesian rivers have great anthropic value as they often constitute the only ways of penetration into the interior of the islands and on their banks are generally aligned villages and non-coastal cities. The rivers, however, have rather irregular flows and in the rainy season they often overflow, violently flooding the plains in which they lazily end their course, thus making it difficult to drain large areas. In Sumatra, the main rivers descend from the inner slope of the Barisan range and run roughly parallel to the NE (Kampar, Indragiri, Musi etc.), crossing vast swampy and floodable areas. In Borneo they descend radially from the central reliefs towards the coasts: towards the western one, like the Kapuas, towards the south, like the Barito, and the eastern one, like the Mahakam; in Java the only important watercourse is the Solo, which flows with a prevalent W direction between the central hills and the northern coast of the island. In the Irian Jaya there are various rivers of significant development, which originate from the Maoke mountains, whose crest line represents the watershed; among the largest are the Digul, which from the southern side of the range turns to the Arafura Sea, and the Mamberamo, which instead descends from the northern slope tributing to the Pacific Ocean. There are few lake basins; the largest is the Toba (1264 km²) on the island of Sumatra, which lies in a basin of the northern hills; other lakes are present in Celebes (Towuti 578 km², Poso 281 km²) and in Borneo (Jempang 225 km², Prian 548 km²).
The climatic conditions feed a very rich vegetation; the dense rainforest prevails, which once covered the entire archipelago with the exception of the eastern islands, where due to the lower rainfall there are large savannah expanses and the presence of tree species that already herald the xerophilous range of Australia. The equatorial forest, with a very dense undergrowth of epiphytes, has remained almost intact in Borneo, but elsewhere, especially in Java, has been partly degraded by man and replaced by crops. Where the vegetal environment has not undergone any alterations, the forest reaches up to 1000-1500 m in height; here it yields to more sparse forests of oaks, lauraceae, conifers; there is no shortage of bamboo forests and mangrove formationsalong the coasts. Indonesia is divided by a deep stretch of sea, known as the Wallace line, into two sectors characterized by an Asian and a European fauna zone; many species are indigenous to an island or group of islands. However, this great variety is threatened by a high risk of extinction. Among the major environmental urgencies are deforestation, caused by the paper industry, the export of timber and a type of intensive agriculture, and water and air pollution. However, there are numerous protected areas, which cover 9% of the territory and also include 67 natural parks, as well as hundreds of other protected areas. L ‘ UNESCO has declared four Indonesian natural sites as World Heritage Sites: Komodo National Park (1991), Ujung Kulon National Park (1991), Lorentz National Park (1999) and the Sumatran Tropical Forest Heritage (2004), considered in danger.