Developers then use that session as a place to store bits of application-relevant data. When a user connects to a server for the first time, a session is created and associated with that connection. These simple chunks of memory are associated with every TCP connection made to a web or application server, and serve as in-memory storage for information in HTTP-based applications. Sessions are the way in which web and application servers maintain state. Sessions Transforming the Stateless into the Stateful That "hack" is where sessions and cookies come into play. In what is certainly one of the most widely accepted, useful hacks in technical history, HTTP was given the means by which state could be tracked throughout the use of an application. Despite the inherently stateless nature of HTTP, it has become the de facto application transport protocol of the web. Applications are built on logical flows and processes, both of which require that the application know where the user is at the time, and that requires state. Traditional applications require some way to maintain their state, while documents do not. Though documents and application protocols are generally text-based, the resemblance ends there. A good example of this is JSON, a key-value pair data format transferred as text.
Even modern uses of HTTP such as that of APIs assume a document-like payload. Unfortunately, HTTP was not designed to be an application transport protocol. The ubiquity of the browser, cross-platform nature, and ease with which applications could be deployed without the heavy cost of supporting multiple operating systems and environments was certainly appealing. Somewhere along the line, HTTP became more than just a simple mechanism for transferring text and images from a server to a client it became a platform for applications.
Its most radical changes involve the exchange of headers and a move from text-based transfer to binary. With the adoption of 2.0, HTTP continued to support a many-request-per-connection model. This was done to address the growing complexity of web pages, including the many objects and elements that need to be transferred from the server to the client. Version 1.1 expanded that ratio to be N:1-that is, many requests per connection. Its first version, 1.0, supported a purely 1:1 request to connection ratio (that is, one request-response pair was supported per connection). HTTP (HyperText Transfer Protocol) was designed to support a stateless, request-response model of transferring data from a server to a client.
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