Online Financial Transactions

I'm developing a website for a company that, in the long run, want to be able to handle financial transactions from their customers online.

I have no idea how to do this

Can someone talk me through how they would go about setting it up? Is it a case of just taking financial details and then the finance department doing their thing with them or do banks have an interface that we can work with?

(I can appreciate that there may be differences between the US and the UK so I'd prefer UK answers but I'm not picky )

Cheers,
Bailz

You'll need to explain what kind of financial transactions they will be doing. There are many different kinds and how you handle them will defer.

I'm relatively new to this whole thing but as far as I'm aware it'll be credit/debit card payment for a service.

What other kinds are there to consider?

If you are going to be accepting payments online then the next question is what country is the client in and what service/product are they offering? This will determine what kind of payment options they have available to them.

You can use a 3rd party Payment Gateway API. Some banks do offer such a service, e.g. HSBC.

I think http://www.protx.com are quite good.

You (your client) will also need a Merchant Account with their bank if they want to accept card payments. There's some advice about that on the protx pages. But if your client already has a merchant account with HSBC, it would probably be best to use the HSBC payment API.