The online Apple Store in the UK, Germany, US and likely other countries suffered some partial outages when the Content Delivery Network (CDN) system failed, resulting in missing images and page design elements.
A CDN is a network of local servers distributed around the world which are used to serve static elements of a website. Instead of a single server in California delivering a photo to a website visitor in Germany, for example, the main website sends an instruction to a German server to display the photo. If the CDN fails, then missing images, CSS elements and Javascript mean that the page design is lost and only the bare content is shown.
As of this morning, all the sites we’ve tried appear to be working properly again.