LAN or WAN or some thing different ?

Distributed processing in LAN or WAN or some thing different from LAN and WAN? Is Bank's ATM's are based on Distributed Processing?

Distributed Processing, more often, refers to Local Area Networks designed in a way that a single program can run simultaneously at various sites. Instead of a single large machine being responsible for all aspects of a process, each separate computer handles a subset of the task. ATM’s are not the part of distributed processing as an ATM machine just provides us an interface to perform our bank transactions. However, distributed processing may be implemented on the back end computer systems (servers) of ATM machines which may be located in different branches.