For merchants who are just starting out a business, choosing the right point-of-sale (POS) terminal for processing credit and debit card transactions can be a complicated task.

There are different types of payment devices out there. POS machines, for example, can be mounted, wired or wireless. There are devices that require a signature or PIN (personal identification number) entry for making payments and there are other facilities that don't.

Andy Brown of ACI Worldwide says making a decision as to what card processing option is best for a merchant will depend on the volume of transaction and the type of business they are doing.

For someone who has a lot of low-value transactions, having a device that has a contactless capability — which means consumers only need to tap or wave their card over a reader — will be a good option.

This device is widely used in venues such as movie theatres, quick service restaurants, convenience stores, grocery outlets and petrol stations.

"A restaurant environment requires the ability to take the terminal to the table so a wireless function is important. Wireless could also be important in some other situations where service is important and you don't want to make the customer go to the terminal to enter their PIN and confirm the transaction," says Brown.

"For situations with a high volume of transactions, then the integration of the PIN pad with the retail till will be appropriate," he adds.