Philately is the study and collection of postage stamps, postal stationery, postal history and other associated subjects. There are stamps of different sizes, shapes and colours focusing on different themes such as art, architecture, flora, fauna, science and technology, sports etc. Stamps have emerged as a vehicle to accord recognition to past and present achievements and to honour and pay homage to individuals, institutions and organisations. Stamps are also used to promote various values and causes such as environmental protection, promotion of tourism, creation of awareness about health and hygiene etc.