In December 2009 Google released new asynchronous tracking code for Analytics tracking on websites. The benefits of this, from the Google blog are:
- Faster tracking code load times for your web pages due to improved browser execution
- Enhanced data collection & accuracy
- Elimination of tracking errors from dependencies when the JavaScript hasn’t fully loaded
The way the new asynchronous code works is that most browsers will load the asynchronous tracking code in parallel with other scripts on the page, thus reducing the web page load time.