The following functions are executed when there is an input in the text field.
1) Defines the url which we should be sent to the server
2) A parameter is added to the content of the input field.
3) A parameter is added to prevent the server from the cache.
4) When a change is triggered statechange is executed
5) An XML HTTP object with a given URL gets executed
6) A request to the server is sent through HTTP.