Map - Selangor

Selangor, also known by its Arabic honorific Darul Ehsan, or "Abode of Sincerity", is one of the 13 Malaysian states. It is on the west coast of Peninsular Malaysia and is bordered by Perak to the north, Pahang to the east, Negeri Sembilan to the south, and the Strait of Malacca to the west. Selangor surrounds the federal territories of Kuala Lumpur and Putrajaya, both of which were previously part of it.

The state capital of Selangor is Shah Alam, and its royal capital is Klang, while Kajang is the largest city. Petaling Jaya and Subang Jaya received city status in 2006 and 2019, respectively. Selangor is one of four Malaysian states that contain more than one city with official city status; the others are Sarawak, Johor, and Penang.

The state of Selangor has the largest economy in Malaysia in terms of gross domestic product (GDP), with RM 239.968 billion (roughly $55.5 billion) in 2015, comprising 22.60% of the country's GDP. It is the most developed state in Malaysia; it has good infrastructure, such as highways and transport, and has the largest population in Malaysia. It also has a high standard of living and the lowest poverty rate in the country.

The origin of the name Selangor is uncertain. A common suggestion is that the name refers to the Malay word langau, a large fly or blowfly that is found in the marshes along the Selangor River (Sungai Selangor) in the state's north-west. According to local lore, a warrior who escaped from Malacca after the Portuguese conquest, took a break from his journey north and rested under a tree here. However, he was disturbed by a persistent fly, whereupon he decided to explore the area. When he found the place to his liking and chose to settle there, he named the place "satu (se) langau" meaning "a large blowfly".

In the absence of a firm etymological explanation, alternative theories abound. One suggestion is that the name may have originated from a kind of tree found in Kuala Selangor and along Selangor River named mentangau. Another theory claims the state's name is derived from the term Salang Ur where ur means "town" or "village" in Tamil, meaning village of the Salang people. It has also been proposed that the name is derived from a combination of salang (stabbing) and jemur (dry in the sun), indicating that it was once a place where traitors were stabbed (salang) then left to roast in the sun (jemur).