The name "Jurong" is often used to collectively describe the region's five main planning areas. However, the URA does not officially recognise all of these places as a single territorial entity. Since the gazetting of the 1998 Master Plan, the Authority has officially classified Jurong as five individual separate planning areas. When Jurong is split into these five contiguous parts, it forms Jurong East and West in the north and north-west, Boon Lay and Pioneer to the south and south-west and Tuas to the extreme west of the region. Each of these individual areas can yet be further divided into subzones, smaller subdistricts that are a part of the larger planning area itself. If all five planning areas are combined, there would be a grand total of 34 subzones in Jurong.