Abstract: The present invention relates generally to a method and apparatus for preparing and processing information to be sent or received via a network, or communicated to or from other data carriers such as smart cards. The present invention describes the construction of a novel “virtual machine” which can be implemented on a device having a minimal amount of hardware, such as hardware which is P used for processing payment transactions (EFTPOS and the like). Prior art DATA/virtual machines tend to slow down operation of the device, as they are effectively acting as an interface between an applications program and the actual device drivers. This is a problem. The virtual machine of the device of the present invention incorporates a virtual message processing means, which is arranged to construct, deconstruct and compare messages and which is applied in the native code of the processor. The message instruction means are provided in the application to direct and control the message processor.