Magento provides a couple of choices for the protocol to use with its Core API; these are:
It's a matter of choice between the two. A few of us would simply decide on preference from previous usage, while some may not be able to use one of the protocols and end up using the alternative. The following information introduces us to both of them, so that we can choose between the two protocols.
SOAP is the newer standard of the two and the most popular. It is also faster in comparison and should be our default choice of protocol, if it is available to us.