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### 1.1 The web and HTTP

The web is a wide-scale decentralised distributed hypertext system, something that's obviously impossible to achieve reliably.

The web is a collection of resources which are identified by URLs, strings starting with `http://`. At any point in time, a resource has a certain value, which is called an instance of the resource.

The fundamental protocol of the web is HTTP, a simple request/response protocol. With HTTP, a client can make a request for a resource to a server, and the server replies with an entity, which is an on-the-wire representation of an instance or of a fragment thereof.