Session flow remains basic allowing it to be investigated and debugged with a HTTP network monitor The client browser automatically converts the messages that arrive on the HTTP stream into appropriate Event objects Uniform Resource Identifiers URIs are used to describe and locate resources on the web and are an essential component in HTTP requests In conditional requests the outcome of a request depends https://wm-lend.ru the value of a validator in the request Each individual request is sent to a server which handles it and provides an answer called the response A project designed to help developers system administrators and security professionals configure their sites safely and securely Range requests are useful for cases when a client knows they need only part of a large file or for cases where an application allows the user to pause and resume a download Request methods indicate the purpose of the request and what is expected if the request is successful Then it delivers them to the event handlers that have been registered for the events type if known or to the onmessage event handler if no type specific event handler was established On the opposite side of the communication channel is the server which serves the document as requested by the client It was designed for communication between web browsers and web servers but it can also be used for other purposes such as machine to machine communication programmatic access to APIs and more Due to the layered structure of the Web stack most of these operate at the transport network or physical levels becoming transparent at the HTTP layer and potentially having a significant impact on performance Users should upgrade to 7 9 x Due to its extensibility it is used to not only fetch hypertext documents but also images and videos or to post content to servers like with HTML form results A server appears as only a single machine virtually but it may actually be a collection of servers sharing the load load balancing or other software such as caches a database server or e commerce servers totally or partially generating the document on demand Cross site HTTP requests are requests for resources from a different domain than that of the resource making the request The client server structure combined with the ability to add headers allows HTTP to advance along with the extended capabilities of the Web New functionality can even be introduced by an agreement between a client and a server about a new header s semantics Cache and authentication methods were functions handled early in HTTP history Clients and servers communicate by exchanging individual messages as opposed to a stream of data This article describes this general structure its purpose and the different types of messages The most common methods are GET and POST for retrieving and sending data to servers respectively but there are other methods which serve different purposes Authentication is a way to verify the identity of a client when making requests to a server There are two types of HTTP messages requests and responses each with its own format Browsers and servers compress their messages before sending them over the network to reduce the amount of data that needs to be transmitted improving transfer speed and bandwidth utilization