brower.js

// this targets Google Chrome and Opera 18+
var isChromium = window.chrome;
if(isChrome === true) {     
  // is chromium based browser
} else {      
  // not chromium based browser
}

//To target if the browser is Google Chrome, use this:
var isChromium = window.chrome,    
    vendorName = window.navigator.vendor;
if(isChromium === true && vendorName === "Google Inc.") {     
    // is Google chrome
} else {      
    // not Google chrome
}

//To target if the browser is Opera 18 or above:
var isChromium = window.chrome,    
    vendorName = window.navigator.vendor;
if(isChromium === true && vendorName === "Opera Software ASA") {      
    // is Opera 18 or above
} else {      
    // not Opera 18 or above
}

//Checking if Firefox:
// check if Firefox
var FF = !(window.mozInnerScreenX == null);
if(FF) {
     // is firefox
} else {
     // not firefox
}

//Checking if IE and IE versions:
// check if IE8-11
var hasDocumentMode = (document.documentMode !== undefined),
    isIE8 = (isDocumentMode === 8),
    isIE9 = (isDocumentMode === 9),
    isIE10 = (isDocumentMode === 10),
    isIE11 = (isDocumentMode === 11);

if(hasDocumentMode) {
     if(isIE11){
           // browser is IE11
     } else if(isIE10){
           // browser is IE10
     } else if(isIE9){
           // browser is IE9
     } else if(isIE8){
           // browser is IE8
     }
}

//If you really need to detect IE7, check for document.attachEvent:
// check if IE7
var isIE7 = (document.attachEvent !== undefined);
if(isIE7) {
     // browser is IE7
} else {
     // browser NOT IE7
}

//Checking for Touch support:
// check if browser has touch support
var hasTouch = !!("undefined" != typeof document.documentElement.ontouchstart);
if (hasTouch) {
     // has touch support
} else {
     // does NOT have touch support    
}