In this chapter, we explored ways in which the code performance can be improved by making optimizations to HTML, CSS, and JavaScript that we write for our applications. It is very important to understand that these are something that may, or may not, benefit you, based on the application that you are trying to build. The main takeaway from this chapter should be the ability to open up the browser's insides and not be scared to dissect and take a look at how the browsers handle our code. Also, be wary that the ECMA specification guide keeps changing, but it takes time for the browsers to catch up with the changes. Also, last but not the least, never over-optimize or optimize too early. If you run into issues, then measure first and then decide what the bottlenecks are before coming up with a plan for optimization.