- Briefly describe both the internet and WWW, the concepts which define them and the differences between them
- Describe and where necessary interpret the Hypertext, Data Mark-up and HTML concepts
- Generate a simple HTML document and publish to City University Web Server
A further more detailed definition: "The Internet, sometimes called simply "the Net," is a worldwide system of computer networks - a network of networks in which users at any one computer can, if they have permission, get information from any other computer (and sometimes talk directly to users at other computers). It was conceived by the Advanced Research Projects Agency (ARPA) of the U.S. government in 1969 and was first known as the ARPANet. The original aim was to create a network that would allow users of a research computer at one university to be able to "talk to" research computers at other universities. A side benefit of ARPANet's design was that, because messages could be routed or rerouted in more than one direction, the network could continue to function even if parts of it were destroyed in the event of a military attack or other disaster. (http://searchwindevelopment.techtarget.com/definition/Internet Accessed 08-10-2010)
"TCP/IP is actually a suite of protocols. TCP or Transmission Control Protocol ensures your data will get to and from its destination. IP or Internet protocol ensures the proper fastest route will be taken."
Read more: http://www.brighthub.com/computing/windows-platform/articles/20609.aspx#ixzz11nsusiGy Accessed 08-10-2010)
Basically the internet is the road the WWW travels on, the infrastructure. Its invention is accredited to Tim Berners-Lee, a MIT professor who "On 25 December 1990, with the help of Robert Cailliau and a young student at CERN, [he] implemented the first successful communication between an HTTP client and server via the Internet." (Wikipedia accessed 08-10-2010)
He is director of the World Wide Web Consortium (W3C) overseeing the continued development of the internet.
World Wide Web: "invented as an internet service that allowed hyperlinked academic documents (web pages to be viewed remotely. "The most widely used part of the Internet is the World Wide Web (often abbreviated "WWW" or called "the Web"). Its outstanding feature is hypertext, a method of instant cross-referencing." (http://searchwindevelopment.techtarget.com/definition/Internet Accessed 08-10-2010) basically the WWW is one tool, using web browsers as a user interface to display web pages, that utilitizes the internet. Other examples of services using the internet email, ftp and telnet (for accessing applications on remote servers as if they were on your own computer).
Its invention accredited to Tim Berners-Lee, a MIT professor who "On 25 December 1990, with the help of Robert Cailliau and a young student at CERN, he implemented the first successful communication between an HTTP client and server via the Internet." (Wikipedia accessed 08-10-2010)
WWW works on client-server architecture, where web-servers (powerful hi speed computers) constantly listen for messages requesting web pages from client computers, armed with a web browser to allow the information returned. The client request a page according to its Universal Reference Locator (URL) broken down, by protocol (http, ftp etc.)://server type (www).domain name (city) .domain (ac.uk) /directory (conditions)/sub-directory(conditionsofuse/file type (html) etc.
Navigation between web pages is possible through he use of HTML (hyper text mark-up language), a natural language system allowing even linking between documents (eg pdfs). Links are embedded into web pages using mark-up elements that contain URLs. Users are unaware of where documents are stored, i.e. which web servers, but will be presented with documents via a suitable browser which interprets the HTML. NB Pages should be saved with the file extension .htm or .html
We call this the "document centered view of information" (Macfarlane Lecture notes 2010)
Other Markup languages such as XML allow web services to be created. (Paraphrased)
Text, images and multipmedia files are just some element making up web pages 'i.e. content' with added styles, semantics (i.e meaning) of the data, applied through using tags.
Eg. anchor tags <a> </a> denotes a hyperlink to a url. <a> href="http://www.bbc.co.uk/" BBC Website </a> shows the text "BBC Website" as click-able and underlined and will open the bbc home page on click.
Attributes can also be added to tags, eg when adding images with the <img> src=pic.jpeg" tag, width="300"' and height="140" we specifiy can the size of the image displayed.
Adding images and files from remote locations, using URL for example allows the "global document centered view of information" (Macfarlane lecture notes 2010) with implications for copyright law, which will be a topic for supplemental reading and appear on the next post.e.g. am I infringing copyright law by displaying the image of Sir Tim Berners-Lee above on this blog?
Practical work in creating, modifying, adding images to web pages using HTML and uploading to the university web pages are exercises carried out in the practical. I shall supplement with work adding content and using HTML tags on my personal website.
I will explore Cascading Style Sheets (CSS) and the syntax used to to create rules for the display and look of the web pages in my website.
Useful how to guide on HTML including using CSS is run by W3C:
http://www.w3schools.com/html/html_intro.asp
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