The charts are commercial monitoring and marketing devices used by the UK music industry to measure its effectiveness in promoting and selling albums, nominally in the field of classical music.
The measurements are made by collating the returns of sales from a number of well-known music stores (high street and online stores) on a regular basis, and this enables a ranking to be established.
For an album to be classified as classical in the charts, it has to have 60% of the playing time dedicated to "classical or traditional music".
Only albums that entirely classical or traditional music qualify for inclusion in the Specialist Classical Albums Chart.
The Specialist Classical Albums Chart was launched in February 2009, having been created in consultation with the record labels' industry body, the British Phonographic Industry (BPI).