Introduction to JavaScript in the first chapter

JavaScript, when born in 1995, is designed to handle form validation on the server side, with the server-side validation changed to a service-side validation, greatly increasing the speed (when the network is slow) today JavaScript is a full-featured language that includes closures, anonymous functions, and even Meta-programming and other features, the Netscape company Langdon. Ike and 1995.2 released LiveScript's scripting language Microsoft blind a few of the high set of its own standards called JScript (the future front-end programmers all hate him) Two version certainly not at that time there is no specification,, so, 1997 to JAVASCRIPT1.1the recommendations of the bit blueprint are presented to the European Computer Federation (ECMA) JavaScript implementation consists of the following three parts of the core ECMAScript Document Object Model DOM browser object model DOM by E CMA-262 The ECMAScript defined by the Web browser is not dependent on the Web browser just one of the possible hosting environments of the ECMAScript implementation, the hosting environment not only provides a basic ECMAScript implementation, but also provides an extension of that language. To enable docking interactions between the language and the environment (such as the DOM), and to use its core capabilities to provide more specific functionality to enable operations for the environment, including node Adobe Flash ECMA-262 no reference to Web browser content The following syntax Type statement keyword reserved word operator object Netscape and IE two sets of DOM standard (more than JAVASCRI PT a scripting language operates on the DOM) at the 1998 DOM1 level becomes the World Wide Web standard DOM1 level is divided into two standard Dom core DOM HTML BOM developers use the BOM to control the parts outside the browser display, BOM different places            Is that there are standards for each browser inconsistency (often causing problems) (HTML5 will normalize the BOM) fundamentally, the BOM only handles browser windows and frames, but people are accustomed to calling all extensions of the browser a part of the BOM (below is a part of it) The function of the pop-up browser window moves the zoom off browser feature provides browser-related details of the Navigator object that provides the browser with detailed information about the page that is provided by the Location object                                                      User Monitor Resolution Details screen object support for cookies think of custom objects like XMLHttpRequest and IE ActiveXObject 

Introduction to JavaScript in the first chapter