(The JavaScript language has been developing steadily: it's not fast, but it never stops. Over the past decade, the image of JavaScript has evolved from a simple toy language to a highly respected programming language, which is used by companies and developers around the world to build incredible applications. Modern JavaScript programming languages are as solid, robust and practical as everIncredibly powerful. Most of the discussion in this book will explain why modern hjavasctip0th and PN are so obviously different. The concept of fencing mentioned in this chapter is born out of wild gossip novels. We will see that the recognition of members has promoted their application and sublimation, and finally formed today's pattern. Well, it's not too late. Let's see what happensWhat is modern JavaScript programming.)