Local file management
Optimizely Configured Commerce lets you upload images and files directly to the web server the Configured Commerce is hosted on, allowing you to host that content. This lets you have your content all in one place, and is usable out of the box within Configured Commerce.
Content Delivery Network (CDN)
A Content Delivery Network (CDN) is a large system of servers across the internet with the intention of providing end users with web content. This content can be in any form, including but not limited to text, downloadable objects, applications, or live streaming media.
Companies often use a CDN (such as Amazon Web Services) because of better performance and availability. Another advantage associated with using a CDN is the cost savings that can come from offloading a significant portion of traffic from servers and network infrastructure of a company's own network resources.
As you can see, multiple people in multiple places can access the content for your website without accessing the same server.