detect.js

function detect() {
    var browser = {};

    var ua = navigator.userAgent,
        msie = new RegExp("MSIE ([0-9]{1,}[\\.0-9]{0,})");
    if (msie.exec(ua) !== null) {
        var rv = parseFloat(RegExp.$1);
        browser.support = !(rv && rv < 9);
    } else {
        browser.support = true;
    }
    
    browser.locale = navigator.language;

    if (navigator.userAgent.indexOf('Win')) browser.os = 'win';
    else if (navigator.userAgent.indexOf('Mac')) browser.os = 'mac';
    else if (navigator.userAgent.indexOf('X11')) browser.os = 'linux';
    else if (navigator.userAgent.indexOf('Linux')) browser.os = 'linux';

    return browser;
};


detect().os;
detect().locale;
detect().support;