People: Brendan Eich (Brandon Aichi)
Background: At that time, the vast majority of Internet users are using speed only 28.8kbit/s "cat" internet, in order to complete the simple form verification, the form data must be sent to the server side to determine whether the user has not filled out a required field, entered an invalid value, Each operation will have to wait more than 30 seconds to have results, which is undoubtedly in the chronic suicide.
In 1997, the European Association of Computer Manufacturers (Ecma,european Computer manufactures association) defined a scripting language standard called ECMAScript (pronounced
The ECMAScript standard consists of syntax, data types, statements, keywords, reserved words, operators, and objects . It does not have any dependencies on the Web browser, and the language itself does not contain input and output definitions. ECMAScript defines only the basis of this language, and on top of that it builds a more complete scripting language.
Web browsers are just one of the hosting environments implemented by ECMAScript, and other hosting environments include Node and Adobe Flash. The hosting environment not only provides a basic ECMAScript implementation, but also provides extensions to the language (for example, DOM, BOM), which use the core types and syntax of ECMAScript to provide more specific functionality.
1997, ECMAScript 1 release.
June 1998, ECMAScript 2 release.
December 1999, ECMAScript 3 release.
In 2000, ECMAScript 4 began brewing, and eventually this version did not pass.
December 2009, ECMAScript 5 release.
In June 2011, the ECMAscript 5.1 edition was released as an international standard.
In June 2015, ECMAScript 6 was formally adopted as an international standard.
Expand reading "Nanyi's ECMAScript 6"
The Document Object model (Dom,document object models) is an application programming interface (API) for HTML that maps the entire page to a multi-tiered node structure. Each component of an HTML page is a node of a certain type, and these nodes contain different types of data. Look at the following HTML page:
<html> <head> <title>Sample Page</title> </head> <body> <p>Hello World!</p> </body></html>
This tree-shaped representation of the document, created by DOM, provides the developer with the initiative to control the content and structure of the page. With the API provided by the DOM, developers can easily delete, add, replace, or modify any node.
Because Netscape and Microsoft are not compatible with the DOM, the World Wide Web Consortium, www Alliance, which is responsible for developing web communications standards, has begun to plan the DOM.DOM Level 1:
Browser object Model (BOM)
2. The DOM level 0 standard does not exist, it is only a reference point in the Dom's historical coordinates.
BOM the most headache is no relevant norms and standards, each browser has a unique implementation, the problem is resolved in HTML5, HTML5 is committed to the many BOM functions written to the formal specifications.Summary
References, errata and questions
Extended reading "standard ECMA-262 5.1 edition"
Extended reading "ecmascript 5 browser compatibility Checklist"
This article is mainly based on the following books, if you need to know more details, you can check the original.
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