1.3.4 Web Technologies

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Created by
Qasim Qayyum

Cards (32)

  • HTML is the language that web pages are written in. HTML allows a browser to render and interpret a webpage for the viewer by describer the structure and the order of the webpage.
  • HTML Language uses tags like this:
    (<tag>, </tag>)
  • There are two sections of a webpage: the body and the head. The head contains the title of the webpage, and the body contains the content of the page.
  • <html> All code written within these tags is interpreted as HTML
  • <body> Defines the content in the main content area of the webpage
  • <link> Used to link to additional files, including CSS stylesheets
  • <head> Defines the browser tab or window heading area
  • <title> defines the text that appears with the tab or window heading area
  • <h1>, <h2>, <h3> Heading styles in decreasing sizes.
  • Paragraphs <p> is used to define a paragraph separated with a line space above and below.
  • Images <img>. No need to include a closing tag when using it. Additional tags such as source <src>, height = x, width = y
  • <a> is an anchor tag that defines a hyperlink with the location paramater.
  • <ol> is used to define and ordered list. Each element within the list is defined using the <li> tag.
  • <div> divides a page into separate areas, each which can be referred to uniquely by name e.g:<div id="page">
  • CSS can be used to specify the way HTML elements look and can be applied to tags such as <H1>, <P>, <div>.
  • CSS can be used in two different forms: internal/embedded CSS or external CSS.
  • Internal CSS is placed inside the style tags and is entered directly into the HTML document.
  • Meanwhile external CSS is written in a separate document and a link to this style sheet is added to the HTML document.
  • To make this internal you would have to add the style tags above the body and below the }.
  • JavaScript is a scripting language which primarily exists to add interactivity to websites
  • The 4th line of code is CSS
  • JavaScript is interpreted rather than compiled, meaning it is done line by line, rather than everything at once.
  • Displaying an alert box:
    alert(“Hello World”); 
  • A search engine is a program that searches through a database of internet addresses looking for resources based on criteria set by the client.
  • Indexing
    1. Search engines rely on an index of web pages. Web crawlers, are used to collect info about websites to build this index
    2. They traverse the internet, web page by web page, using links on websites.
    3. Web crawlers collect keywords/phrases from linked webpages and adds this info to the index.
    4. They also collect and add meta data from websites (data about data)
  • There are 2 factors to determine how a page is ranked:
    1. How many incoming links it has from other webpages.
    2. The page rank of web pages linked to it.
  • Application Programming interface (API) = set of built in tools used for building software applications.
  • damping factor is the probability that a user will not press on a link
  • Server side processing is when a client sends data to a server for it to be processed. This means no information is processed on the client computer
  • Server side advantages:
    1. More secure
    2. Does not require any plugins.
    3. Not browser dependent
    4. Further validation
  • Client side processing is when a client processes the data on a local device. This means that all of the information is processed on the client computer.
  • Client side advantages:
    1. Executes quickly
    2. Webpage can immediately respond to user actions
    3. Reduces unnecessary server processing.