Of course everyone wants his or her shopping system to be secure. People are using their credit cards on your website and it would be a nightmare scenario for any business to have this compromised. The same applies to the data that you gather about the customers in your forms. It would be a serious issue if either type of data was taken by a hacker and used.
Sadly there are thousands of unscrupulous people out there who spend a lot of time trying to break into online systems. You read about it every day online, in the newspapers and on TV. In Ireland even recently political parties had their websites hacked. So no system is perfect. All we can do is use the best technologies that are available to us at the time.
Your ecommerce developer does not write the security he uses the security of the systems that he implements. All of these companies are on top of their games an monitor changes in the market. If and when (and it does happen) a security glitch does happen they release updates to their software to fix or patch their systems.
What this means is that every system that has ever been implemented to handle online shopping will have regular updates required. The hackers can also download these systems and they can pore over the software to try and find security holes.
Before you get too worried this is a rare exception and in reality should not happen to your system if you use the latest cart software, keep it up to date and use a regulated payment provider.
If you wish to handle the payment part on your own system you will pay for a security certificate (we will discuss this on another document) and this needs to be kept up date as much as any other part of your system.
So in summary your system is safe. We would be out of business if they were full of holes. But good housekeeping is essential, regular backups, implementation of fixes when they become available and using secure servers for your shop and the right payment providers.
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