CDN
Also known as: Content delivery network, Edge network
A CDN is a distributed network of servers that delivers a website's files from a location physically near each visitor.
In full
A content delivery network is a geographically distributed set of servers that caches a website's files and serves them from a location close to each visitor, rather than every request travelling to a single origin server. Because network latency is bounded by physical distance, this can remove a substantial share of loading time for distant visitors. A CDN also absorbs traffic spikes, since cached responses never reach the origin, and most providers include protection against denial of service attacks. For statically generated sites the entire site can be served from the edge, making the origin's location largely irrelevant to visitor experience.
Why it matters
For a New Zealand business with international visitors, or an overseas business selling into New Zealand, a CDN resolves most of the hosting-location argument. Round-trip time from Auckland to Europe is roughly 250 milliseconds; from an edge node it is a fraction of that.