How do you accept a debit or credit card for you or your company for online transactions?

Perhaps the easiest way to utilize EFT (Electronic Fund Transfer) online is by using PayPal, a service provided through eBay for personal or business use. PayPal offers several different service options that can be found on their website which is linked below in this answer. If you need to develop a business website or platform for payment and you have a larger business base, PayPal offers integration services that can seamlessly add transaction capability to your website without having to utilize PayPal's website directly. This is a good option if you are trying to create a more streamlined website for a more developed organization. Otherwise, the personal/business service works well and is more affordable.