Basic Attention Token (BAT) is an ERC20 token built on top of Ethereum. It launched its crowdsale in May 2017 which saw the tokens fully subscribed and raised $35 million in 30 seconds. The Basic Attention Token aims to fix digital advertising, which is broken, fraudulent and opaque. Basic Attention Token work by having advertisers pay BAT to website publishers for the attention of users. Users will also receive BAT from the advertisements that is being served to them. By using the blockchain, digital advertising will be more transparent. Basic Attention Token is created by the team that built the Brave browser, an open-source, privacy-focused browser that blocks ads and trackers. The browser measures user attention and rewards publishers for users attention.