Basically any transaction occurring in the financial system will have a charge attached to it on both sides of the transaction.

FORBES: Balanced Budget And Comprehensive Tax Reform Made Simple ? The Automated Payment Transaction Tax

Green group leader Rebecca Harms said that there needed to be wide ranging reform of Europe's banking system such as banning hedge funds and introducing a financial transaction tax, a call echoed by Lothar Bisky, the leader of the far-left group.

BBC: European Parliament