Why? Because word of mouth only gets you so far in the internet era. People discover new businesses—even local business—via Bing, Google, and Yahoo. The days when they'd just look you up in the yellow pages are long gone. If you don't have a sharable website address, your chances of building online word of mouth via social networking plummet, too. In other words, no website, no discoverability, no money. Of course, web hosting isn't just for businesses. You may want to host a personal website or blog, too. Either way, the services here have you covered.
A Content Distribution Network (CDN) is a network of servers distributed geographically. The purpose of a CDN is to deliver content on the internet much faster. If a user in Toronto is trying to access your website, the closest server to them will take care of this. But someone coming to your website from Sydney, Australia, will be catered to by a server closest to them. The main host server holds your website content, and all the other servers have a cached version each.
That means that, even though there may be multiple virtual machines on the same physical server, you are in an isolated environment with dedicated resources (RAM, Storage) and virtually allocated CPUs that no one else can touch. Plus, with root access, you can make technical changes that would not be allowed on a shared hosting plan. You get the advanced performance, control and flexibility usually reserved for dedicated servers, but at a much lower price.
BigCommerce is a bit different from our other hosting plans in that it's a SaaS (software-as-a-service) provider instead of an IaaS (infrastructure-as-a-service) provider. In other words, rather than renting space on a virtual machine where you setup and configure your own site, BigCommerce provides you with an app you login to that creates and online store.