We were asked a while ago to explain the difference between shared web hosting and a virtual private server (VPS) and as VPS is a term some folks will be unfamiliar with, so I'll share the explanation here as well. Think of this in terms of your website being a person rather than a webspace and it all makes sense...
Shared hosting: We use resources on a shared server but have to share all the server resources with every other user on the same server. It's like is a house or flat shared by a group of friends. Each person has their own bedsit [website, i.e. the board] but share a bathroom [MySQL server] and kitchen [PHP scripting] as well as the building structure [server] and entrance way [internet connection.] If one flatmate wants to take a bath it impacts on other flatmates' use of the bathroom... lots of overlaps between users of resources means that some days we can't have a bath or even wash up cos everyone else's run off all the hot water [server connection failures].
Virtual Private Hosting: We are one of a small fixed number of users on a server. The server is split using special software into sections, each of which has shared use of the server hardware and internet connection but exclusive use of their own section, thus ring-fencing the resources allocated to that section. Back to the flat share analogy, this time we're in a block of self-contained flats where each occupant has their own bedroom bathroom and kitchen [website, PHP scripting, MySQL server] but where only the building itself [server] and the entrance way [internet connection] are shared with the other occupants of the block, so we can take a bath when we want and no-one else can use our water!
