Mastertronic was originally a publisher and distributor of low-cost computer game software founded in 1983. Their first games were distributed in mid-1984. At its peak the label was the dominant software publisher in the UK, a position achieved by selling cassette-based software at £1.99. As well as supplying leading retailers such as Woolworth's and Toys "R" Us, Mastertronic sold software in outlets such as newsagents which had not been previously associated with the software market.