function createRequest() {
	try {
		request = new XMLHttpRequest();
	} catch (microsoft) {
		try {
			request = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (old_microsoft) {
			try {
				request = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (failed) {
				request = null;
			}
		}
	}
	return request;
}

function sendGetRequest(request, url, callback) {
	request.open("GET", url, true);
	request.onreadystatechange = callback;
	request.send(null);
}