The Basic Attention Token (BAT) is an ERC20 token developed to address the problems on digital advertising market. It will be used as a unit of exchange for a decentralised, blockchain-based digital advertising platform. In this platform, there will be three main users which are the advertisers, the publishers and the users. The advertisers will give BATs to the publishers based on the attention of the users, while the users receive some BATs for participating in the platform. Such platform will be able to deliver fewer ads, but more relevant advertisements to targeted users. At the same time, with the transparency of the platform, advertisers will be able to receive better reporting and performance on their ads.