function userAgent() {

    var browserType = "";
    if (navigator.userAgent.indexOf("MSIE") != -1) {
        browserType = "IE";
        return browserType;
    }
    if (navigator.userAgent.indexOf("Firefox") != -1) {
            browserType = "FF";
            return browserType;
    }
    if (navigator.userAgent.indexOf("Mozilla") != -1) {
            browserType = "MZ";
            return browserType;
    }
    if (navigator.userAgent.indexOf("Opera") != -1) {
            browserType = "OP";
            return browserType;
    }
    if (navigator.userAgent.indexOf("Safari") != -1) {
            browserType = "SF";
            return browserType;
    }
    if (navigator.userAgent.indexOf("Mac") != -1) {
            browserType = "MC";
            return browserType;
    }
    browserType = "NG";  
    return browserType;
}