A barcode is a decodable identification mark that is attached with products. When decoded with a machine, it either leads you to the seller's website or a payment platform, according to what's set by the seller. The mark is in the shape of a square constituting of black and white lines that are parallelly distributed to formulate a unique algorithm.
Barcode standards are established and managed by GS1, a non-profit organization which was initiated by the Ministry of Commerce and Industry in 1996.