The GET method

The GET method is used to ask for a specific document - when you click on a hyperlink, GET is being used. GET should probably be used when a URL access will not change the state of a database (by, for example, adding or deleting information) and POST should be used when an access will cause a change. The semantics of the GET method changes to a "conditional GET" if the request message includes an "If-Modified-Since:" header field. A conditional GET method requests that the identified resource be transferred only if it has been modified since the date given by the "If-Modified-Since:" header. The conditional GET method is intended to reduce network usage by allowing cached entities to be refreshed without requiring multiple requests or transferring unnecessary data.