GSS codes are nine-character geocodes maintained by the United Kingdom's Office for National Statistics (ONS) to represent a wide range of geographical areas of the UK, for use in tabulating census and other statistical data.
The aim was to produce a set of areas of consistent size, whose boundaries would not change (unlike electoral wards), suitable for the publication of data such as the Indices of Deprivation.
Lower Layer Super Output Areas (LSOAs) typically contain 4 to 6 OAs with a population of around 1,500.
Middle Layer Super Output Areas (MSOAs) on average have a population of 7,200.
[citation needed] MSOAs use the name of the local or unitary authority followed by three digits, for example "Tower Hamlets 022" which is E02000885.