Post on 13-Jan-2016
AS Level ICT
Selection and use of appropriate software: Web browsers
Web-related software
• With the exponential growth of Internet usage, the need for specialist software that allows users to interact with it has also grown
• The most common web-related software in use includes:– Web browsers– Email software– Website authoring software
Web browsers
• A web browser is software that interprets the markup of files in HTML, formats them into Web pages, and displays them to the user
• Examples of browsers include: Internet Explorer, Netscape Navigator, and Firefox
Web browsers
Internet Explorer – when opened, the web browser will either display a blank page or will open a pre-set webpage (in this example the Google search engine web page)
Web browsers
• It is possible to access any web page that has been submitted by its creator to the World Wide Web using a web browser unless:– The web browser is installed on a network that
has been set up to exclude certain categories of web page (e.g. game sites, web pages that contain adware, pornography, community sites [YouTube, MySpace, Facebook])
– The web browser is installed on a stand-alone computer that has ‘parental control’ software installed on it (e.g. Weblocker, K9, Spector Pro)
Web browsers
• It is possible for users to access email facilities via a web browser
Web browsers
Clara.net is one of many ISPs (Internet service providers)
Their customers can access their emails via a portal from the clara.net website
Web browsers
The webmail portal allows access to an ISP customer’s emails
Web browsers
When the hotlink is clicked …
Web browsers
… a login page appears onscreen
Once their user name and password have been entered, the customer can access their emails
• Despite the fact that most users can access their emails via their web browser and their ISP’s website, many prefer to use dedicated email software (e.g. Outlook Express)
• Most email systems use SMTP (Simple Mail Transfer Protocol – a protocol for sending email messages) to send emails from one server to another
• The emails can then be retrieved with an email client using either POP (Post Office Protocol) or IMAP (Internet Message Access Protocol)
• The correct POP or IMAP server and SMTP server have to be specified when email software is being configured
• Email software usually has a number of useful facilities, including:– Create – this allows the user to compose an
email– Reply – this allows the user to compose a reply
to an email that has been received– Search – this allows the user to search their
archive of sent and received emails by originator, addressee, subject, or date
In this example, to create an email the user clicks ‘New’ …
In this example, to create an email the user clicks ‘New’ and a new window – where the email can be composed – is launched
In this example, to reply to an email the user clicks the ‘Reply’ icon …
In this example, to reply to an email the user clicks the ‘Reply’ icon and a new window – where the reply can be composed – is launched
The ‘Search’ facility enables the user to search the ‘Inbox’ folder for received emails by originator, subject, or date
The ‘Search’ facility enables the user to search the ‘Inbox’ folder for received emails by originator, subject, or date
The same facility can be used to search ‘Drafts’, ‘Outbox’, and ‘Sent Items’ folder
– Forward – this allows the user to send a copy of a received email – often with a covering message – to a third party
– Address book – this allows the user to save the email addresses of people to whom they wish to send emails or who have sent them emails (the latter can be done automatically)
The ‘Forward’ option allows the user to forward (i.e. send) a copy of an email they have received to a third party
When the ‘Address book’ option is clicked …
When the ‘Address book’ option is clicked, the searchable address book appears on screen
– Groups – this is a section within the address book where the user can group addressees together, so that an email sent to the group will go to everyone in the group; this can speed up the time taken to send the same message to a large number of people
– Attachments – this allows the user to attach files or folders to an email so that copies of documents, spreadsheets, photographs etc. can be sent via the Internet to other people
Once an email has been composed, files and folders can be attached to it by clicking the ‘Add Attachment’ icon
A new dialogue box will then appear, and by using the ‘Browse’ facility, the file or folder to be attached to the email can be found …
A new dialogue box will then appear, and by using the ‘Browse’ facility, the file or folder to be attached to the email can be found and attached
Search engines
• The most used search engines (e.g. Google, Yahoo, Ask) are natural language interfaces that allow the user to search the Internet
• They are crawler-based search engines (as opposed to human powered directories) that create their listings automatically
• They use special programs (‘crawler’ or ‘spider’ programs) to go through the World Wide Web looking for and at websites that they can index
• Users can then search through what the ‘crawlers’ or ‘spiders’ have found and indexed
Search engines
• To search the World Wide Web using a search engine, the user must create a query
• The query can be quite simple, a single word at minimum
• Creating a more complex query requires the use of Boolean operators that allow the user to refine and extend the terms of the search
Search engines
• The Boolean operators most often seen are: – AND – This ensures that all the words joined by
"AND" must appear in the web pages (N.B. some search engines substitute "+" for AND)
– OR – This ensures that at least one of the word joined by "OR" must appear in the web pages
– NOT – This ensures that the word or words following "NOT" must not appear in the web pages (N.B. some search engines substitute "-" for NOT)
Search engines
– FOLLOWED BY – This ensures that one of the word or words must be directly followed by the other
– NEAR – This ensures that the word or words must be within a specified number of words of the other
– Quotation Marks – The words between the quotation marks are treated as a phrase, and that phrase must be found in the web page
Search engines – Comparison of search results
The results of a search using the words ‘search’ and ‘engine’
Search engines – Comparison of search results
The results of a search using the phrase ‘search engine’
Search engines – Comparison of search results
The results of a search using the phrase ‘search’ AND ‘engine’
Search engines – Comparison of search results
• The results of these searches produced similar but not identical results
• This is because of the way in which the Boolean operators honed down the search, the last being more precise than the first (211,000,000 results as opposed to 66,500,000 results)
• It is also a reflection of the way in which web designers have used particular design features to ensure that their websites are prioritised by a search engine
Search engines – Comparison of search results
Search criteria Number of ‘hits’
‘crown’ ‘woods’ ‘school’ 292,000
‘crown’ AND ‘woods’ AND ‘school’ 14,500,000
“crown woods school” 8,820
How many hits would a Google search produce for the following search criteria?
crown woods school
crown AND woods AND school
“crown woods school”
Website design features
• Websites usually have one or more of the following design features:– Logo – this helps to identify the website,
particularly ones belonging to commercial or government organisations
– Navigation – unless the website only has a single web page, users will need to navigate their way around the website; a navigation bar (navbar) is a common method used to achieve this
Website design features
– Search facility – this enables the user to find something particular on the website; sometimes search facilities will also enable the user to undertake a full Internet search from within the website
– Hotlinks – these are words or phrases that, when clicked, lead the user to another part of the website or the Internet
– Hotspots – these are images that, when clicked, lead the user to another part of the website or the Internet
Website design featuresLogo Navigation Search
Hotlinks
Hotspots
Website design featuresLogo Navigation Hotlinks
Website design featuresLogo Navigation Hotlinks
Hotspots
Website design featuresLogo Navigation Search
Hotspots
Hotlinks
Website design features
• Web designers also use frames or tables to layout each webpage
• Frames enable a designer to set up a page that actually shows several web pages at once; this is usually done so that the Header and/or Footer and/or Sidebar that are seen remain the same whatever the main content of the web page is showing
Website design features
This example shows fames being used so that the main content of the webpage covers most of the screen whilst the website navigation is in the sidebar frame
This example shows fames being used so that three different pages can be ‘nested’ together
Website design features
• Frames have tended to fall out of favour with web designers over recent years because some web browsers do not cope well with them
• Tables have tended to be used in place of frames recently because they allow the web designer to layout each webpage exactly how they want visitors to see them, regardless of the web browser that is being used or the screen resolution the web page is being viewed at
Website design features
A web page viewed at a screen resolution of 800 x 600
Website design features
A web page viewed at a screen resolution of 1024 x 768
Website design features
A web page viewed at a screen resolution of 1280 x 960
Website design features
• In this example, the web page has been optimised for the 1024 x 768 resolution; when viewed at 800 x 600 the whole of the web page cannot be seen, and when viewed at 1280 x 960 the web page has stretched to fill the screen
• A web designer should take this into consideration when designing a website, and the use of tables – which can be pre-set to a particular width – is a very useful tool for ensuring that their design is WYSIWYG (What You See Is What You Get)
Web authoring software
• The language used to create web pages is HTML (HyperText Markup Language)
• This is a relatively easy to learn programming language that uses a mixture of natural language and abbreviated commands and keyboard symbols
Web authoring software
This example of HTML shows the use of natural language and abbreviated commands and keyboard symbols
Natural language command
Abbreviated command
Keyboard symbol
Web authoring software
• Typing in HTML commands takes time, and it is far quicker for a web designer to use web authoring (or web design) software to create a web site
• The facility to create web pages exists in several applications (e.g. Microsoft Word, Microsoft Publisher) but specialist web authoring software has more functions available for the web designer to use
Web authoring software
• The following programs are commonly used by web designers to create web pages:– Microsoft FrontPage– Macromedia Dreamweaver– Serif WebPlus
Web authoring software
Microsoft FrontPage
Web authoring software
Macromedia Dreamweaver
Web authoring software
Serif WebPlus
Web authoring software
• All the examples shown have similar functions that make them effective web authoring software:– The ability to add and format text (including
changing font size, font colour, line spacing, and paragraph justification)
– The ability to create frames– The ability to add and use tables so that the
layout can be WYSIWYG (What You See Is What You Get), regardless of the screen resolution of the viewer’s computer monitor
Web authoring software
– The ability to import data from other applications (e.g. text that has been word-processed, images that have been manipulated)
– The ability to add hyperlinks to other web pages– The ability to anchor together different sections
on a web page– The ability to add mailto links (i.e. a link that
automatically launches the viewer’s email application so that they can create a pre-addressed)
Web authoring software
– The ability to preview web pages before they are uploaded
– The ability to test view the web page in different web browsers
– The ability to allow the web designer to view – and change where necessary – the HTML created by the web authoring software
Web authoring software
– The ability to use cascading style sheets (CSS) – this is a simple mechanism for adding style (e.g. fonts, colours, spacing) to web pages
– The ability to create forms that can be used to collect data; these can be used in conjunction with databases
AS Level ICT
Selection and use of appropriate software: Web browsers