26 Basic concepts and technologies of the Web

26 Basic concepts and technologies of the Web

Web development is more of a bother, need to master a lot of things, especially in front-end development of friends, need to pass 10 lines. Today, this article introduces beginners to some basic concepts and techniques used in web development, from A to Z a total of 26 items, each corresponding to a concept or technology.

A-ajax

AJAX is all called "asynchronous JavaScript and XML" (Asynchronous JavaScript and XML) and is a web development technique for creating interactive Web applications. According to Ajax author Jesse James Garrett suggested that Ajax:

• Use XHTML+CSS to represent information;
• Use JavaScript to manipulate the DOM (Document Object Model) for dynamic display and interaction;
• Using XML and XSLT for data exchange and related operations;
• Asynchronous data exchange with the Web server using the XMLHttpRequest object;
• Use JavaScript to bind everything together.

Similar to DHTML or Lamp,ajax does not refer to a single technique, but rather organically utilizes a range of related technologies. In fact, some Ajax-based "derivation/composition" (derivative/composite) technologies are emerging, such as Aflax.

B-browser

A Web browser is a software that displays files in a Web server or file system and lets users interact with those files. It is used to display text, images, and other information on the World Wide Web or local area network. These words or images can be hyperlinks that connect to other URLs, and users can quickly and easily navigate through the various information. Most Web pages are in HTML format, and some Web pages require a specific browser to display correctly. A common web browser on a PC is the market share of Microsoft Internet Explorer, Mozilla Firefox, Google Chrome in January 2010, Opera from Apple's Safari and Opera software company. The browser is the most frequently used client program. Web developers should make sure that their programs work properly in every major browser.

C-css

Cascading style sheet, also known as: string Style list , English:cascading style Sheets, shorthand for CSS, defined and maintained by the standard, A computer language used to add styles (fonts, spacing, colors, and so on) to a structured document, such as an HTML document or an XML application. Currently, the latest version is CSS 2.1, which is the candidate recommendation standard for the consortium. The next version of CSS 3 is still in the process of development.

D-dom

The Document Object Model , or DOM, is the standard programming interface recommended by the Organization for the processing of extensible superscript languages. Document Object model dates back to the late 1990, when Microsoft and Netscape's "Browser Wars" (browser wars), in order to make life and death in JavaScript and JScript, So large-scale to give the browser a powerful function. Microsoft has added a number of proprietary things to Web technology, including VBScript, ActiveX, and Microsoft's own DHTML format, making it impossible for many Web pages to be displayed using non-Microsoft platforms and browsers. Dom is the masterpiece of the time.

E-events

An event is an action that can be recognized by a control, such as pressing the OK button, selecting a radio button, or a check box. Each control has its own identifiable events, such as loading of forms, clicking, double-clicking, and so on, the text of the edit box (text box) changes things, and so on, and modern web applications rely heavily on event-driven.

Events have system events and user events. System events are triggered by the system, such as the time of day every 24 hours, the deposit date of the bank depositors increased by one. User events are fired by the user, such as when a user taps a button to display a specific text in a text box. The event-driven control performs a function. The object that triggers the event is called the event sender, and the object that receives the event is called the event receiver.

Using an event mechanism can be implemented: when a state of a class object changes, the system invokes a method in the class for handling the event, or the object that triggers the control event invokes the control for all registered event handlers, and so on.

F-firebug

Firebug is a Web browser Mozilla Firefox extension, is a debugging tool. Users can use it to debug, edit, and even hack any Web site's CSS, HTML, DOM, and JavaScript code. Firebug also offers other web development tools, such as Yahoo! 's Web Speed optimization suggestion Tool YSlow. Firebug was written by Harvey (Joe Hewitt). He was one of the original Firefox founders.

G-grid

grids , also called Rasters , are, by definition, more accurate. Find a more appropriate definition of the Web grid system: A regular grid array to guide and standardize the layout of the page and the distribution of information. The Web grid system is developed from a planar grid system. For web design, the use of grid system can not only make the information of Web page more beautiful and readable, but also more usability. And, for the front-end development, the Web page will be more flexible and normative. If you have many CSS frameworks that support raster functionality, refer to the article "introducing 27 Classic CSS frameworks."

H-html

Hypertext Markup Language (English:hypertext Markup Language,HTML) is a banner that is designed for "web page creation and other information that can be seen in Web browsers." HTML is used to structure information-such as headings, paragraphs, and lists-and can also be used to describe the appearance and semantics of a document to some extent. The original definition was given by Tim Berners-Lee, which was further developed by the IETF using the simplified SGML (Standard universal Labeling language) syntax, which later became an international standard maintained by the World Wide Web Consortium.

The latest version is HTML5 It is the next major revision of HTML and is still in the development phase. The goal is to replace the 1999 set of the HTML 4.01 and XHTML 1.0 standards, in order to enable the rapid development of Internet applications, the network standards to meet the needs of modern network. When it comes to generalized theory and HTML5, it actually refers to a set of technical combinations including HTML, CSS, and JavaScript.

I-ie

Windows Internet Explorer(formerly known as Microsoft Internet Explorer, abbreviation for Internet Explorer, abbreviated IE ), is a Web browser launched by Microsoft Corporation. As of September 2010, statistics show that Internet Explorer has a market share of up to 59.65%. While it is still the most widely used web browser, the market share is more than 30% compared with the peak of 2003.

Internet Explorer has a degree of support for a number of standardized technologies, but there are also many operational gaps and compatibility failures that have led to increasing criticism from technology developers. The increase in criticism has largely been attributed to Internet Explorer's competitors who have provided full technical support, and the application of standard specifications (Standards-compliant) has become more widespread. Because Internet Explorer is widely used globally, web developers often find vulnerabilities in Internet Explorer, a private set of features, and imperfect support for standards when they look for cross-platform code.

The Internet Explorer 9 browser released on March 14, 2011 dramatically increased support for the CSS3 and HTML5, which is the first GPU-accelerated version of the Internet Explorer browser. The official version gained 95/100 points in the ACID3 test, making great strides compared to previous versions. It can be argued that the Internet Explorer browser's support for the specifications is no longer a problem, starting with Internet Explorer 9.

J-javascript

JavaScript is a scripting language widely used in client-side web development, often used to add dynamic functionality to HTML pages, such as responding to user actions. Originally designed by Netscape's Brendan Eich, it is a dynamic, weakly-typed, prototype-based language with built-in support classes. JavaScript is a registered trademark of Sun Corporation. ECMA International has developed a ECMAScript standard based on JavaScript. JavaScript can also be used in other contexts, such as server-side programming. The complete JavaScript implementation consists of three parts: ECMAScript, Document Object model, byte order notation.

Netscape Company initially named its scripting language LiveScript to Netscape after working with Sun to rename it to JavaScript. One of the purposes of JavaScript, originally inspired by Java, was to "look like Java", so there are syntax similarities, and some names and naming conventions are borrowed from Java. But the main design principle of javascript stems from the approximation of self and scheme.javascript with the Java name, which was the result of Netscape's agreement with sun for marketing purposes. To gain a technical advantage, Microsoft has introduced JScript to the scripting language of JavaScript. For interoperability, ECMA International (formerly the European Association of Computer Manufacturers) created the ECMA-262 Standard (ECMAScript). Now both belong to the realization of ECMAScript. Although JavaScript is promoted and advertised as a scripting language for non-programmers, rather than as a programming language for programmers, JavaScript has a very rich nature.

K-keyword optimization

keyword optimization , also called Search engine optimization (search engine Optimization, abbreviated SEO is a search engine based on the rules to improve the destination site in the search engine rankings in the way. Many studies have found that search engine users tend to only pay attention to the first few items of search results, so many sites want to influence the search engine by various forms of sorting. In particular, a variety of advertising-dependent websites.

The so-called "processing for the search engine optimization" is meant to make the site more easily accepted by search engines. The search engine will compare the content of the site to each other, and then the browser will show it to the searchers in the quickest and most complete way.

Search engine optimization for any website, to be successful in the promotion of the site, search engine optimization is a key task. At the same time, with the search engine constantly changing their ranking algorithm rules, each time the change of the algorithm will let some good ranking site in one night Mingluosunshan, and the loss of the direct result of the ranking is the loss of the site's inherent substantial traffic. So every time the search engine algorithm changes will cause a small disturbance and anxiety in the website. It can be said that search engine optimization is an increasingly complex task.

L-less

Less is the first Ruby gem to have CSS with dynamic language features, including variables, operators, and nested rules. The real effect of less is to convert CSS using advanced features into standard CSS. These are done via HTTP handler when the Web client initiates the request. It can also be done at the time of editing. In addition, less can be configured to automatically minimize the generated CSS files, not only saving bandwidth, but also making the end user experience a higher level. In addition there are. NET version of less.

M-mvc

The MVC pattern (model-view-controller) is a software architecture model in software engineering, which divides the software system into three basic parts: model, view and controller. The MVC pattern was first proposed by Trygve Reenskaug in 1974 and is a software design pattern invented by Xerox PARC in the 1980s for the programming language Smalltalk (Palo Alto). The purpose of the MVC pattern is to implement a dynamic program design that simplifies the subsequent modification and expansion of the program, and makes it possible to reuse a part of the program. In addition, this mode makes the program structure more intuitive by simplifying the complexity. By separating the basic parts of the software system, it also gives the functions of each basic part.

N-node.js

Node is a JavaScript runtime, which in fact encapsulates the Google V8 engine (applied to Google Chrome). The V8 engine executes JavaScript very fast and performs very well. Node optimizes some of the special use cases, providing an alternative API that allows V8 to run better in a non-browser environment. For example, in a server environment, it is often necessary to process binary data, but JavaScript has insufficient support for this, so V8. Node adds the buffer class for easy and efficient processing of binary data. As a result, node not only uses V8, but also optimizes it to make it more resilient in all environments. node. JS is all-encompassing, but the main point is that it provides a way to run JavaScript outside of a Web browser. JavaScript is widely used in front-end development of Web sites. Node enables this popular programming language to run in more environments, even on the server side of the Web site.

O-object

object , which is a term in object oriented that represents a specific thing in the objective World problem Space (Namespace), and represents the basic element in the solution space of a software system. In software systems, objects have unique identifiers, objects include attributes (properties) and Methods (Methods), and properties are information that needs to be remembered, by the services that the object can provide. In object-oriented software, an object is an instance (Instance) of a class (oriented).

p-php

PHP(Hypertext Preprocessor) is a scripting language that runs on a computer, primarily for handling dynamic Web pages, and also for command-line run interfaces Line interface), or create a graphical user interface (GUI) program. PHP was first invented by Rasmus Lerdorf in 1995, and now PHP's standards are maintained by the PHP group and the open source community. PHP uses PHP license as the license agreement, but because this protocol restricts the use of PHP names, it is incompatible with the Open Source License Agreement GPL.

The scope of application of PHP is quite extensive, especially in the development of web-based programs. Generally speaking, PHP runs mostly on a Web server and runs PHP code to generate Web pages that users view. PHP can run on most servers and operating systems, and using PHP is completely free. Based on April 2007 statistics, PHP has been installed on more than 20 million websites and 1 million servers.

Q-query

query , there are a lot of meanings. For example, the query language is used to interact with the extended system that stores the data, and a good example is SQL for manipulating relational databases. Another meaning is that a query string, as part of a URL, is used to pass data in a Web application, and the format of the query string is typically a key-value pair form.

R-regular Expressions

Regular Expressions (English: Regular expression, regex, or RegExp, abbreviated as RE), also translated into formal notation , conventional notation , in computer science, Refers to a single string that describes or matches a series of strings that conform to a certain syntactic rule. In many text editors or other tools, regular expressions are often used to retrieve and/or replace text content that conforms to a pattern. Many programming languages support the use of regular expressions for string manipulation. For example, in Perl, a powerful regular expression engine is built in. The concept of regular expressions was initially popularized by tools software (such as SED and grep) in Unix.

S-source Control

source Code control, also known as Versioning , is a software engineering technique that ensures that the same program files that are edited by different people are synchronized during the development process. Software designers often use versioning to track and maintain changes in source code, files, and settings, and to provide procedures to control these changes. In the simplest case, software designers can keep many different versions of a program themselves and make appropriate numbering for them. This simple approach has been used in many large software projects. This is a way to achieve the goal, but not efficient enough. In addition to maintaining many of the same code backup at the same time, and relying heavily on the self-cultivation and development discipline of software designers, this is often the cause of errors.

Sometimes it is necessary for a program to have more than two versions at once, for example: In a version for deployment, the bug has been fixed, but no new features have been added, and in another development there are new features being developed and new errors to be resolved, which makes the same time require different versions and modifications. In addition, in order to find a program error that exists only in a particular version, or to find out which version of a program error occurred, the software-debugging user must also borrow a different version of the code to find out where the problem is.

T-tdd

test-driven Development (Test-driven development) is one of the methods of modern computer software development. Use testing to drive the design and implementation of software programs. The test drive began to pop in the 1990s. Test-driven development is a program development approach advocated in extreme programming, mainly by writing a test program before coding it to pass the test. The goal of test-driven development is to get quick feedback and use the "illustrate the main Line" method to build the program.

The analogy of test-driven development. Development can be viewed from two aspects: the function and quality of implementation. Test-driven development is more like the development of two hats thinking method, first put on the implementation of the function of the hat, under the aid of the test to quickly achieve the correct function; then put on the reconstructed hat, under the protection of the test, by removing redundant and duplicated code, improve the reusability of the code, and achieve the quality improvement. Visible testing in test-driven development does belong to the core position, throughout the development of the always.

U-unit Testing

Unit Testing (also known as Module testing ) is a test of correctness checking for program modules (the smallest unit of software design). The program unit is the smallest testable part to be applied. In procedural programming, a unit is a single program, function, process, etc. for object-oriented programming, the smallest element is a method, including a base class (superclass), an abstract class, or a method in a derived class (subclass).

In general, programmers every time the program is modified at least one unit test, in the process of writing a program is likely to conduct several unit tests to verify that the program to meet the requirements of the Software specification (en:specification) objectives, no bugs; Although unit testing is not necessary, But it is not bad, it involves the policy decision of project management.

V-vim

Vim is a text editor developed from VI. Code completion, compilation and error jumps and other convenient programming features are particularly rich, in the programmer is widely used. And Emacs are a favorite editor for Unix-like system users. The first version of Vim was released by Bram Moolenaar in 1991. The initial abbreviation is vi imitation, and as the function continues to increase, the official name is changed to vi improved. It is now free software released in open source mode.

W-wordpress

WordPress is a blog platform developed using the PHP language that allows users to set up their own blogs on servers that support PHP and MySQL databases. WordPress can also be used as a content management system (CMS) to use. WordPress is a free open source project authorized for release under the GNU General Public License. The latest version is the official Simplified Chinese version of the 3.0.5, which is released on February 24, 2011, and is available in several languages, including English.

X-xss

Cross-site Scripts (cross-site scripting, often referred to as XSS) are a security vulnerability attack on a Web site application that allows malicious users to inject code into a Web page. Other users will be affected when they view the Web page. Such attacks typically include HTML and the user-side scripting language.

Y-yui

Yahoo! UI Library (YUI) is an open source JavaScript library that uses code techniques such as ajax,dhtml and DOM in order to create a highly interactive Web page. It also contains a number of CSS resources.

Z-z Index

Z-index is a CSS property that sets the stacking order of elements. Elements that have a higher stacking order are always in front of elements that are lower in stacking order. This property sets the position of an anchored element along the z axis, defined as the axis that extends vertically to the display area. If positive, it is closer to the user and a negative number means farther away from the user.