1.3.4 Web Technologies

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Created by
Yanuu .

Cards (24)

  • Html- used to create web pages. Is the content of the page.
  • CSS- the design/layout of the webpage
  • Basic HTML tags:
    • <body> the main content
    • <head> browser tab/window heading area
    • <title> a title
    • <h1>,<h2>,<h3> heading styles
    • <p> paragraph
  • Image HTML tag:
    <img src = 'location', height='x', width='y'>
  • To make a list in HTML:
    • <ol>(numbered) or <ul>(bulleted)
    • <li> 'text'
    • </ol> or </ul>
  • To devide a page, use <div>, </div>
  • To embed CSS in HTML:
    <style>, </style>
  • JavaScript- an Interpreted language allowing web features to be added easily.
  • JavaScript advantages:
    • Allows complex tasks to be performed relatively easily.
    • Can execute 'on the fly' and does not need to be compile.
    • Enables the addition of dynamic and interactive activities to web pages.
  • JavaScript features:
    • Drawing and animations
    • Manipulation of HTML elements such as text and images
    • Navigation tools such as tabs
    • Web form validation before transmission
  • JavaScript can be embedded directly into a webpage or within external script files linked into a HTML page
  • JavaScript Input:
    • Commonly used to process data on the users machine as it is entered
    • This may validate data, animate objects or provide other inactivity
    • Once data has been processed, it may be passed on to a server
  • JavaScript Function:
    • Function- block of code that is designed to be repeatedly called
    • Functions perform specific tasks that the user may wish to carry out multiple times
    • Functions are executed once they are invoked and are otherwise idle in the background
  • JavaScript Alert box:
    • alert(text)
  • Search Engines- systems that locate resources on the world wide web.
  • Search Engine Indexing
    • Has an index which keeps a record of the resources located on the WWW
    • The process of creating an index includes using a peice of software called a web crawler or spider
  • Web crawler- internet bots that continuously crawl the web to discover and record publicly available web pages.
    • They look at webpages and follow hyperlinks located on those pages
    • Continues to follow the hyperlinks on other pages
    • Keeps a record in the index
  • Web Crawlers store information such as:
    • URL of the resource 
    • Content of the resource
    • Recent update time
    • Quality of resource
    The information will be stored in the index
  • Meta Tags- describe the content of the webpage
    • Web developers can place meta tags inside HTML pages to make the page more likely to be formed
    • Hidden from users but discoverable by web crawlers
  • Page Rank- lists search results in the order and rank of usefulness and relevance.
  • Original Page Rank algorithm:
    PR(A) = (1-d)+d(PR(Ti)/C(Ti)+...+PR(Tn)/C(Tn))
    • PR(A)- pagerank of page A
    • PR(Ti)-pagerank of pages Ti which links to page A
    • d- damping factor
    • C(Tn)- The number od outbound links on Page Ti
  • Page Rank algorithm:
    • The algorithm does not rank websites as a whole
    • Each web page as it's own page rank
    • The page rank of page A is defined by the page rank of those page linked to page A
  • Damping factor- the probability of a random web browser reading a page. Damping factor is usually set to 0.85.
  • Page Rank Factor
    There are around two hundred factors that affect a page rank
    These include:
    • Domain name
    • Frequency of search item
    • Age
    • Frequency of page updates
    • Magnitude of content updates
    • Keywords in <h1> tags