A Few days back I play with Vagrant and trying to figure out the source of the virtual machine image that Vagrant use.
I learned that it download from cloud-images.ubuntu.com.
Site performance is a method to measure how fast your site loads on desktop and mobile devices. Most of the techniques are similar both some are specific to mobile. This method is also known as Web Performance Optimization or Website optimization.
Steve Souders coined web performance term around 2004. Long before people optimize the website by optimizing the backend apps, optimizing hardware, look for packet loss, etc. Web Performace techniques try a different approach where it tries to make the site load faster and displayed faster so it will give a better experience to the user.