How To Get Data From Server

What i want to do is that this function post data to the server (ASP) and
the server will response with 'OK' My question is how can i send data clientside from Javascript to the server ? (navigate ? with url ?)

and check the returned data in the same function ?

function ShowData(TxtArt)
{
alert(TxtArt + ' : ' + parent.frames.Bottom.TxtUsrName.value + ' - ' +
parent.frames.Bottom.TxtRemarque.value); // testing purpose
// post the data to the server. ex .. myURL.asp?userID=1000&Art=ART1201
// fetch the data from the server. to verify if the 'OK' is recieved ->
the server will response with 'OK'
// if 'ok' -> i will update clientside an frame (ex. contents of
shoppingbasket)
}

Any idea's ?