Design and Implementation of Web pages

Introduction to Web Development lecture one,

•In 1990 and 1991,Tim Berners-Lee created the World Wide Web at the European Laboratory for Particle Physics (CERN) in Geneva, Switzerland

•The original purpose of the World Wide Web (WWW) was to provide easy access to cross-referenced documents that existed on the CERN computer network

•Hypertext linking allows you to quickly open other Web pages

•A document on the Web is called a Web page

•A Web page is identified by a unique address called the Uniform Resource Locator (URL)

•A URL is also commonly referred to as a Web address

•A URL is a type of Uniform Resource Identifier (URI)

•A Web site refers to the location on the Internet of the Web pages and related files

Web pages are displayed using a program called a Web browser

•A Web server is a computer that delivers Web pages

•The most popular Web server software is Apache HTTP Server (Apache)

•The second most popular Web server is Microsoft Internet Information Services (IIS) for Windows

HTML Documents

•Web pages are created using Hypertext Markup Language (HTML)

•Web pages are commonly referred to as HTML pages or documents

•A markup language is a set of characters or symbols that define a document’s logical structure

•HTML is based on an older language called Standard Generalized Markup Language (SGML)

•Like SGML, HTML was originally designed as a way of defining the elements in a document independent of how they would appear

•HTML has evolved into a language that defines how elements should appear in a Web browser

•Understanding HTML is critical in learning how to write a web application along with the server programming

•HTML documents are text documents that contain formatting instructions called tags

•HTML tags include:

–Formatting commands (boldface or italic)

–Controls that allow user input (option buttons or check boxes)

•Tags are enclosed in brackets (< >) and consist of an opening tag and a closing tag

•Tutorial for learning HTML

–http://www.htmldog.com/

–http://www.w3schools.com/html/DEFAULT.asp

Web Communication Protocols 

•A Web page is identified by a unique address called the URL

•Each URL consists of two basic parts:

–A protocol (usually HTTP) and

–Either the domain name for a Web server or a Web server’s Internet Protocol address 

•Hypertext Transfer Protocol (HTTP) manages the hypertext links that are used to navigate the Web

•A host refers to a computer system that is being accessed by a remote computer

•A domain name is a unique address used for identifying a computer such as a Web server on the Internet

•The domain identifier identifies the type of institution or organization (.biz, .com, .edu, .org)

•An Internet Protocol, or IP address, is another way to identify computers or devices connected to the Internet

•An IP address consists of a series of four groups of numbers separated by periods

•Each Internet domain name is associated with a unique IP address

•HTTP is a component of Transmission Control Protocol/Internet Protocol (TCP/IP)

•Hypertext Transfer Protocol Secure (HTTPS) provides secure Internet connections for transactions that require security and privacy

Publishing Your Web Site

•Web Hosting: 

–The publication of a Web site for public access

–Internet access (cable modem, DSL, satellite, dial-up modem, ISP) 

•Internet Service Provider (ISP)

–Provides access to the Internet along with other types of services such as e-mail

•ISP advantages to hosting a Web site:

–Extremely fast Internet connections using advanced fiber-optic connections

–Large and powerful Web servers and the expertise and manpower to maintain and manage them

•A domain name is a unique address used for identifying a computer, such as a Web server on the Internet

Publishing Your Web Site (continued)

•Domain name registration

–Pick a domain name that is similar to your business name or that describes your Web site

–You cannot use a domain name that is already in use or a trademarked name

–Contact a domain name registrar to find out the availability of a domain name and register it

–Domain names are stored in a master database that is maintained by the InterNIC

–For a fee, domain names can be registered for a specified period of time

–Most hosting sites provide registration service for you

–After you register your domain name, notify your ISP of your domain information

•File Transfer Protocol (FTP) 

–Is a TCP/IP protocol used for transferring files across the Internet

–Transfers files between an FTP client (your computer) and an FTP server (a server capable of running FTP)

–The vehicle that allows you to get your Web page files to the Web server

–Your ISP provides a username and password to log on to the FTP site and upload files to the FTP server

–Examples of FTP clients include Firefox and Internet Explorer and WinScp

•Use your browser to log on to an FTP server and upload your files

Working with Well-Formed Web Pages

•HTML became an Internet standard in 1993 with the release of version 1.0

•The current version of HTML (4.01) was released in 1999

•HTML 4.01 is the last version of the HTML language and is being replaced with extensible hypertext markup language (XHTML)

•HTML is not suitable for user agents other than Web browsers 

 Thank's for reading this lecture  and wait for the next lecture.