Sunda Islands, mainly in Indonesia, between the South China Sea and the Indian Ocean, comprising the western part of the Malay Archipelago. It includes two main groups: the Greater Sunda Islands, to which belong the largest islands of Borneo, Sumatra, Java, and Sulawesi; and the Lesser Sundas, which lie E of Java and include Sumbawa, Flores, Timor, and Sumba (the largest islands). Bali and Lombok, although smaller, are the most important of the Lesser Sundas. The Lesser Sundas, which were renamed Nusa Tenggara [southeastern islands] in 1954, form two provinces within Indonesia. Malaysia, Brunei, and East Timor are the other nations wholly or partially in the Sunda Islands. The Sunda Strait, 20 to 65 mi (32-100 km) wide, between Java and Sumatra, connects the Java Sea with the Indian Ocean.

Archipelago extending from the Malay Peninsula to the Moluccas. The islands make up most of the land area of Indonesia, with only northern and northwestern Borneo and the eastern portion of Timor not under Indonesian political control. They include the Greater Sunda Islands (Sumatra, Java, Borneo, Sulawesi, and adjacent smaller islands) and the Lesser Sunda Islands (Bali, Lombok, Sumbawa, Sumba, Flores, Timor, Alor, and adjacent smaller islands). Most of the islands are part of a geologically unstable and volcanically active island arc. Malay cultures and languages predominate in the area.

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