Client-Server Web Apps with JavaScript and Java

Chapter 2. JavaScript and JavaScript Tools

JavaScript is most despised because it isn’t SOME OTHER LANGUAGE. If you are good in SOME OTHER LANGUAGE and you have to program in an environment that only supports JavaScript, then you are forced to use JavaScript, and that is annoying. Most people in that situation don’t even bother to learn JavaScript first, and then they are surprised when JavaScript turns out to have significant differences from the SOME OTHER LANGUAGE they would rather be using, and that those differences matter.

—Douglas Crockford

Thus Douglas Crockford summarizes JavaScript as the language that many use but few learn. His book goes on to identify parts of the language that are legitimately useful and powerful and points out others that are truly problematic and best avoided. If you are a programmer required to extensively use JavaScript, it simply makes sense to take the time and energy to study it thoroughly. Crockford’s approach makes the programmer’s learning task more manageable by effectively ignoring large parts of the language and focusing on a powerful and concise subset.

In addition to learning JavaScript itself (later standardized under the name ECMAScript), you need to invest time learning about the specific programming environment. While other languages run on underlying operating systems, relational databases, or host applications, JavaScript was designed originally to run in a browser. The ECMAScript Language Specification explicitly states this.

ECMAScript ...