What is the fine-grained topic of the following text: Henry began developing terminals for electronic funds transfers at the retail point-of-sale in 1987, and for ten years he single-handedly developed the software running on payment terminals for many financial institutions, including American Express, First Data, National Australia Bank, Paymark New Zealand, Thai Military Bank, Cashcard Australia, Colonial State Bank, and Papua New Guinea Banking Corporation. Only return the topic.
Henry's development of software for electronic funds transfer terminals