JavaScript

1. Java Script Module 2. World Wide Web (WWW) 3. Web Terms 4. NEED FOR SCRIPT 5. Introduction to Internet Programming 6. CLIENT SIDE and SERVER SIDE Scripting 7. Different Scripting Languages 8. Introduction to JavaScript 9. JavaScript and Security 10. How to Enable JavaScript 11. Advantages of Java Script 12. Limitations with JavaScript 13. Difference between JavaScript and JAVA 14. Difference between JavaScript and VBScript 15. JavaScript Development Tools 16. JavaScript Programming Techniques 17. JavaScript terms 18. Starting with JavaScript Programming step by step 19. Time to start JavaScript Programming 20. JavaScript Variables 21. JavaScript RESERVED WORDS 22. JavaScript Data Type 23. NUMBER DATA TYPE 24. BOOLEAN DATA TYPE 25. STRING DATA TYPE 26. NULL DATA TYPE 27. JavaScript Undefined DATA TYPE 28. JavaScript Operators 29. JavaScript Arithmetic Operators 30. JavaScript Logical Operators 31. JavaScript Comparison Operators 32. JavaScript String Operators 33. Bit Manipulation Operators 34. JavaScript Assignment Operators 35. JavaScript Conditional Operator 36. Conversion between JavaScript Data Types 37. Alert JavaScript function 38. confirm JavaScript function 39. prompt JavaScript function 40. JavaScript Statements 41. Single line & Multi-line Comments 42. JavaScrip If Statement 43. JavaScript if..else Statements 44. JavaScript If…else..if statement. 45. JavaScript For Statement 46. JavaScript For..in Statement: 47. JavaScript While Statement 48. JavaScript do while Statement: 49. JavaScript break and continue statement 50. JavaScript switch Statement: 51. JavaScript function() 52. JavaScript function with a Return Value 53. JavaScript with Statement 54. try, catch, and throw Statements 55. JavaScript ARRAY 56. JavaScript array of different data types 57. JavaScript ARRAY and Bubble sorting Program 58. JavaScript Array Methods 59. concate() method 60. every() method 61. filter() method 62. forEach() method 63. indexOf() method 64. Join() method 65. lastIndexOf() method 66. map() method 67. reduce() method 68. reduceRight() method 69. reverse() method 70. some() method 71. toSource() method 72. toString() method 73. pop() method 74. push() method 75. shift () method 76. slice () method 77. splice () method 78. sort() method 79. unshift() method 80. EVENT handling with JavaScript 81. onblur JavaScript Event 82. onchange JavaScript Event 83. onclick JavaScript Event 84. onDblClick JavaScript Event 85. onfocus JavaScript Event 86. onkeydown JavaScript Event 87. onkeyup JavaScript Event 88. Onkeypress JavaScript Event 89. onLoad JavaScript Event 90. onMousedown JavaScript Event 91. onMouseup JavaScript Event 92. Onmouseover JavaScript Event 93. onmouseout JavaScript Event 94. onMouseMove JavaScript Event 95. onReset JavaScript Event 96. onsubmit JavaScript Event 97. onUnload JavaScript Event 98. The Screen Object 99. JavaScript Interview Part1 100. JavaScript Interview Part2 101. JavaScript Interview Part3 102. JavaScript Interview Part4 103. JavaScript Interview Part5 104. JavaScript Interview Part6 105. JavaScript Interview Part7 106. JavaScript Interview Part8 107. JavaScript Interview Part9 108. JavaScript Interview Part10
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Web Terms tutorials

  • Before you proceed further, it becomes extremely necessary to understand following terms like:

    1. BROWSER

    2. CLIENT

    3. SERVER

    4. DOMAIN

    5. URL

    6. LAN

    7. WAN

    8. HTML

    9. CSS

    10. Plug-ins

    11. Helper Application

    12. MIME

    13. CGI

    14. APPLETS

    15. ACTIVE-X

 

1) BROWSER

  • A web browser is a software application which enables a user to display and interact with text, images, videos, music, and other information that could be on a website.

  • Text and images on a web page can contain hyperlinks to other web pages at the same or different website.

  • Web browsers allow a user to quickly and easily access information provided on many web pages at many websites by traversing these links.

  • Most Popular browsers are such as:

    1. Chrome: Google Chrome is a browser that combines a minimal design with sophisticated technology to make the web faster, safer, and easier. The latest version of Google Chrome is 27.0.1438.7

    2. Firefox: Firefox is a product of the Mozilla Foundation. The latest version of Firefox is Firefox 21.

    3. Internet Explorer: Internet Explorer (IE - created by Microsoft) is a very prominent web browser for the Windows OS. IE is the most popular web browser. It comes pre-installed on all Windows computers. The latest version of IE is IE10. 

    4. Safari: Safari (created by Apple) is a very popular web browser among Apple computers. Safari is also the native browser on the iPhone and iPod touch. The latest version of safari is 6.0.2.

    5. Opera: Opera (created by the Opera Software Company) is another fairly popular web browser. It handles common Internet-related tasks. Opera also includes features such as tabbed browsing, page zooming, mouse gestures, and an integrated download manager. The latest version of opera is 12.15.


 

2) CLIENT:

  • A client is a computer program that, as part of its operation, relies on sending a request to another computer program.

  • When you connect to Internet, your computer will act as Client.

  • Types: Client computers and devices are either Fat clients, Thin clients, or hybrid clients.

Fat Client :

    1. A fat client, also known as a rich client or thick client, is a client that performs the bulk of any data processing operations itself, and does not necessarily rely on the server.

    2. The fat client is most common in the form of a personal computer, as personal computers operate independently.

    3. For example, a computer running a CAD program (such as AutoCAD or CATIA) that ultimately shares the result of its work on a network is a fat client.

Thin Client:

    1. A thin client is a minimal sort of client .Thin clients use the resources of the host computer

    2. A thin client's job is generally just to graphically display pictures provided by an application server, which performs the bulk of any required data processing.

    3. A device using web application (such as Office Web Apps) is a thin client.

Hybrid Client:

    1. A hybrid client is a mixture of the fat Client and Thin client models. Similar to a fat client, it processes locally, but relies on the server for storage data. 

    2. This approach offers features from both the fat client (multimedia support, high performance) and the thin client (high manageability, flexibility). A device running the video game Diablo III is an example of hybrid client.

 

3) SERVER:

  • It is also known as HOST. It is a computer, which responds to the request asked by clients. It is computer, which stores all files, information, Database of web sites.

  • A server is a physical computer (a computer hardware system) dedicated to run one or more services, to serve the needs of the users of other computers on a network. 

  • In a general network environment the following types of servers may be found.

    1. Application Server, a server dedicated to running certain software applications

    2. Database server, provides database services to other computer programs or computers

    3. Catalog server, a central search point for information across a distributed network

    4. Communications Server, carrier-grade computing platform for communications networks

    5. Compute server, a server intended for intensive (esp. scientific) computations

    6. Fax server, provides fax services for clients

    7. File server, provides remote access to files

    8. Game server, a server that video game clients connect to in order to play online together

    9. Home server, a server for the home

    10. Name server or DNS (Domain Name System)

    11. Print server, provides printer services

    12. Proxy server, acts as an intermediary for requests from clients seeking resources from other servers

    13. Media Server, provides multimedia broadcasting, streaming of audio and video.

    14. Stand-alone server, a server on a Windows network that neither belongs to nor governs a Windows domain

    15. Web server, a server that HTTP clients connect to in order to send commands and receive responses along with data contents

  • Some of the Popular Web Servers are:
    1. Apache server from Apache,

    2. Microsoft IIS servers from Microsoft,

    3. Nginx from Nginx ins.

    4. GWS servers from Google.


4) DOMAIN:

  • The Domain Name System (DNS) helps users to find their way around the Internet.

  • Every computer on the Internet has a unique address – just like a telephone number, every host computer on Internet has IP address. It stands for "Internet Protocol".

  • A domain name "extension" is called a "top-level domain (TLD)." These are divided into three different categories: generic top-level domains (gTLD), country code top-level domains (ccTLD) and infrastructure top-level domains.

  • Generic top-level domains are the ones most frequently seen on the Web:

.com (originally intended for use by commercial organizations but is available to anyone).

.net (originally intended for use by sites directly related to the Internet but is available to anyone).

.org (originally intended for use by non-profit organizations but is available to anyone).

.edu (used by educational organizations).

.gov (reserved for agencies of Government).

.mil (reserved for the military).

.int (reserved for int. organizations established by treaty. i.e. the European Union: http://europa.eu.int).

.aero (reserved for members of the air transport industry).

.biz (for use by businesses only).

.coop (reserved for cooperative associations).

.info. (informational related sites but is available to anyone)

.mobi (sites catering to mobile devices)

.museum (reserved for museums).

.travel (travel agents, airlines, hoteliers, tourism etc)

.name (reserved for individuals and familiy).

.pro (being developed for professionals and related entities).

 

  • The next top-level domains are the two letter country codes. These are used to designate a country or a dependent territory. For instance, in the URL http://www.telegraph.co.uk, the "uk" represents the United Kingdom. A listing of all country codes can be found on the IANA Web site. IANA (Internet Assigned Numbers Authority) oversees the allocation of all TLD's.

  • The top-level domain infrastructure is limited to ".arpa" and is used exclusively for Internet-infrastructure purposes. The .arpa designation comes from the United States Department of Defense Advanced Research Projects Agency, the government agency which formulated the Internet.

 

5) URL:

  • URL Stands for Universal Resource Locator. When any one wants to visit any web site, one has to type its Universal Resource Locator (URL) into address space bar of Browser.

  • URL contains information about the location of the Web document. For e.g.

http://www.cbtSAM.com/index.aspx

  • URLs, or Uniform Resource Locators, are the method by which documents or data are addressed in the World Wide Web. The URL contains the following information:

    1. The internet name of the site containing the resource (document or data)

    2. The type of service the resource is served by (e.g., HTTP, Gopher, WAIS)

    3. The Internet port number of the service. If this is omitted the browser assumes a commonly accepted default value.

    4. The location of the resource in the directory structure of the server.

    5. The following is an outline of the most common form of a URL:

 

http://www.siteaddress.com:8080/path/subdir/file.php

 

http

Service

www.siteaddress.com

Host

8080

Port Number

/path/subdir/file.php

File and resource details

 

6) LAN:

  • LAN Stands for Local Area Network. When more than one computer are connected together it is called network. LAN, allows to connect computers which are installed within local Office, Premises or Building.

  • Most local area networks are built with relatively inexpensive hardware such as Ethernet cables, network adapters, and hubs. Wireless LAN and other more advanced LAN hardware options also exist.

  • Examples: The most common type of local area network is an Ethernet LAN. The smallest home LAN can have exactly two computers; a large LAN can accommodate many thousands of computers. Many LANs are divided into logical groups called subnets. An Internet Protocol (IP) "Class A" LAN can in theory accommodate more than 16 million devices organized into subnets.

 

7) WAN:

  • WAN Stands for Wide Area Network. Using various devices and technologies like high speed phone line, Fiber optic cable, Wireless satellite and microwave links, WAN can connect two or more computer that can covers a larger geographical area.

  • Using WAN, one can connect computers situated in different Metro Cities, States or even Countries.

  • A WAN differs from a LAN in several important ways. Most WANs (like the Internet) are not owned by any one organization but rather exist under collective or distributed ownership and management.

  • WANs tend to use technology like ATM and  Frame Relay  for connectivity over the longer distances.

 

8) HTML:

  • HTML stands for Hyper Text Markup Language. It is the basic tool for all web page development for Web sites you see on Internet.

  • HTML was originally developed by Tim Berners Lee at CERN. Since then there have been major changes incorporated in different versions.

  • Officially it is W3C (World Wide Web Consortium) at MIT (Massachusetts Institute of Technology) to define and establish new version of HTML. However W3C have no powers to bind software leaders.

  • Therefore Microsoft and Netscape regularly come up with their own extensions to official HTML.

  • HTML Version 2.0 was released on October 7, 1995.

  • Added the capabilities to include forms within Document

  • HTML Version 3.0 was released on July 21, 1996

  • Added tags for tables and supports Java Script and Java in document

  • HTML Version 4.0 was released on January 1999.

  • Since 1999, HTML 4 version. It supports international text, greater accessibility, generic object, dynamic style sheet and many more features.

  • HTML 3.2 had been named as WILBUR.

  • HTML 4.0 had been named as COUGAR.

  • HTML Version 5.0 was probably released on January 2011.

  • Some of the most interesting new features in HTML5 are below:

    1. The <canvas> element for 2D drawing

    2. The <video> and <audio> elements for media playback

    3. Support for local storage

    4. New content-specific elements, like <article>, <footer>, <header>, <nav>, <section>

    5. New form controls, like calendar, date, time, email, url, search.

  • HTML has extension .htm or .html

9) CSS:

  • Stands for Cascading Style Sheet. It is an extension of HTML.

  • It allows greater control over browser in way each element are laid out and displayed.

  • CSS was developed by W3C (World Wide Web Consortium) and introduced with HTML 3.2 version. Beware while using CSS with Netscape – check it thoroughly.

  • The main purpose of CSS is to define the presentation of HTML elements

  • All styles are defined and stored in Style sheets

  • After storing styles in a separate style sheet files, these are added into HTML documents.

  • Defining the style outside the html document helps in saving lots of work and time

  • CSS allows you to define more than one style in one style sheet; known as the cascading of styles

  • Example: if you want to change the color of the body of your HTML document into black; then body would become the selector because you are selecting the body part of the html document to be changed.

Body {color : black}

  • You can also add multiple properties and values in the same line of code using semi colon. For instance

P {text-align : right ; color : blue}

 

10) Plug-Ins

  • Plug-ins are small program. The metafile tells the web browser to launch the appropriate program player. Those players are plug-ins.

  • Plug-ins allows developers to expand the browsers’ ability. So features not supported by IE or NE can be developed and at any point when browser refers those files it allows to download and install those plug-ins.

  • Plug-ins help the browser process special types of web content, like Flash or Windows Media files.

  • On Windows, Mac, or Linux? Chrome supports most popular plug-ins:

    1. Adobe Flash Player

    2. Adobe Reader

    3. Java

    4. Windows Media Player

    5. Real Player

    6. Quick Time

    7. Microsoft Silver light

 

11) Helper Application

  • A helper application is an external viewer program launched to display content retrieved using a web browser.

  • Most GUI web based browser allows, to view files like .GIF or .JPEG, some browser even play audio files. Instead of developing larger and complicated browsers that support each and every type of files, most browsers use Helper Application when it comes across file related to those applications.

  • Example: Some common examples include Windows Media Player and QuickTime Player for playing streaming content.


 

12) MIME

  • Stands for Multipurpose Internet Mail Extension. MIME was originally developed as a standard for handling different types of files in E-mail. These include text in languages other than English using character encodings other than ASCII, and 8-bit binary content such as files containing images, sounds, movies, and computer programs.

  • MIME identifies file types using "TYPE/SUBTYPE" naming scheme.

  • Some of the common MIME types are

    1. Text/plain Refers to Normal ASCII text file

    2. Text/HTML Refers to HTML file

    3. Image/gif Refers to Graphics Interchange Format file

    4. Image/jpeg Refers to Joint Photographic Experts Group Format file

    5. Video/mpeg Refers to Moving Pictures Experts Group format file.

 

13) CGI:

  • The CGI specifies how external programs might be used on Server. CGI programs are used to process data submitted from browser.

  • It allows performing database searches. And ways to add, modify and delete database. CGI program or Script works on LINUX based server.

Or

  • Common Gateway Interface (CGI) is a standard method for web server software to delegate the generation of web content to executable files. Such files are known as CGI scripts or simply CGIs; they are usually written in a scripting language.

 

14) APPLETS:

  • APPLETS are program, developed under JAVA. Applets is an application, designed to be transmitted over the, Internet and executed by, JAVA compatible browsers.

  • JAVA language was developed by Sun Microsystems, inc. As JAVA is platform independent programming Language, i.e. it follows the principle of Write Once and Run Everywhere. Program written using JAVA can run on any OS like Windows / Linux or Solaris without any modifications.

  • Advantages of Applet:

    1. Applets are cross platform and can run on Windows, Mac OS and Linux platform

    2. Applets can work all the version of Java Plug-in

    3. Applets runs in a sandbox, so the user does not need to trust the code, so it can work without security approval

    4. Applets are supported by most web browsers

    5. Applets are cached in most web browsers, so will be quick to load when returning to a web page

    6. User can also have full access to the machine if user allows

15) Active- X:

  • Active-X is Microsoft’s approach to execute objects other than java applets. Custom controls have changed Windows programming.

  • ActiveX controls can be used to enhance web development. The Win32API the OLE (Object Link) custom control. Now it is called as ActiveX controls.

  • Microsoft first introduced the term ActiveX at the Internet Professional Developers Conference in March of 1996.

  • ActiveX referred to the conference slogan "Activate the Internet" and was more a call-to-arms than a technology or architecture for developing applications. 

  • In a very short time, it has become Microsoft's answer to the Java technology from Sun Microsystems.  An ActiveX control is roughly equivalent to a Java applet.

  • The difference is that while ActiveX controls can interface with Microsoft Windows better than Java, they only offer limited cross-platform support.  Currently, ActiveX controls run in Windows 95/98/NT and in Macintosh.

  • ActiveX controls can be created using a variety of languages or development tools, including C++, Visual Basic, PowerBuilder, or with scripting tools such as VBScript.

 

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