Search Engines, Metadata and Accessibility “How to make your web pages prominent”
Agenda What will we cover today? • • Search Engines Metadata Accessibility – Why? – What? – How? – Demonstration Questions
Search Engines What is a Search Engine? • • • Software that enables users to search the Internet or Intranet using keywords. A program that acts as a catalogue for the Internet or Intranet. A web search tool that automatically visits websites (using crawlers), records and indexes them within its database, and generates results based on a user's search criteria. Popular Search Engines
Search Engines How do they work? • Web Crawling Automated “spider” that follows links and then analyses content in pages to determine what should be indexed. Metadata is very important in this phase. • Indexing Data about web pages are stored in an index database for use in later queries. Some search engines, such as Google, store all or part of the source page (referred to as a cache) as well as information about the web pages. • Searching & Results The engine looks up the index and provides a listing of best-matching web pages according to its criteria. The usefulness of a search engine depends on the relevance of the result set it gives back.
Search Engines University Search Engine Statistics • • • The University uses Microsoft Share. Point Portal Server 2003 ~88, 000 web pages are crawled every day The crawl starts at 6: 00 am every day The crawl takes ~ 20 minutes to complete The search engine is currently crawling: – www. unisa. edu. au – www. unisanet. unisa. edu. au – www. library. unisa. edu. au
Search Engines How Share. Point ranks pages 1. Document or Page Title <title>Test Page</title> 2. Metadata keywords <meta name="keywords" content=“test page, testing"> 3. Metadata description <meta name="description" content=“This is a test. ”> 4. 5. Content Frequency of search words in entire document or page
Search Engines When I search I don’t get good results … Four possible causes: • No Content There is no content that matches your search query. • Bad search phrases You are putting in really bad search phrases! • Bad search engine The search engine isn’t very good, or isn’t searching the content that it should be. • Bad content The content that you want exists, but the metadata and text within the page is not optimised for a search engine.
Metadata Information • Metadata is ‘data about data’. • The use of metadata is included in the World Wide Web Consortium's accessibility recommendation because metadata makes documents easier to find and use. • Metadata enhances accessibility, whilst also enhancing usability for everyone. • Important web metadata: – Page Title – Keywords and Description
Metadata Page Title • The page Title of an HTML document is a descriptive name that appears in the title bar of the web browser when the browser is displaying that page. • It also appears in bookmarks, your history file listed in 'go' or 'history' menus, and is used by search engines. It is essential therefore that each page has a clear, meaningful title indicating its contents. Example: School of Computer and Information Science, Uni. SA
Metadata Keywords • The Keywords field should convey the subject matter of the webpage or resource. • Keywords should be expressed as words or phrases that describe theme or content of the webpage or resource. Try to imagine the terms someone outside your area would use in a search engine to find information on your web pages. As a guide: – – always choose the most significant and unique words do not repeat keywords unnecessarily use both upper and lower case letters for initialisms and/or acronyms include synonyms, acronyms, alternative word endings, different spellings (eg color/colour; Student and Academic Services/SAS) Example: SWSP, School of Social Work and Social Policy, swsp, social work and social policy
Metadata Description • The Description field should contain a brief textual description of the content of the webpage or resource. This may include abstracts or summaries, or content descriptions. • Use complete sentences and good grammar; some search engines will use this summary in your displayed search results. Example: Home page for University of South Australia, located in Adelaide, South Australia
University Search Demonstration on how to implement metadata in Front. Page
University Search Demonstration comparing pages with metadata and those without
Web Accessibility What is Web Accessibility? • Web accessibility means that people with disabilities can use the Web. More specifically, Web accessibility means that people with disabilities can perceive, understand, navigate, and interact with the Web, and that they can contribute to the Web accessibility also benefits others, including older people with changing abilities due to aging. • “The power of the Web is in its universality. Access by everyone regardless of disability is an essential aspect. ” -Tim Berners-Lee, W 3 C Director and inventor of the World Wide Web
Web Accessibility The aim for the University • Provide access to all Uni. SA web pages to the broadest range of community members • Creating web pages that support the use of assistive technologies – screen readers – alternative keyboards – text enlargers
Web Accessibility Who is supported by Web Accessibility? • People with disabilities – vision, eg. blindness, colour blindness – hearing, eg. deafness, reduced hearing capacity – physical, eg. paralysis – cognitive, eg. dyslexia • People in rural and remote areas • People using old hardware, software or with technical limitations • Older people
Web Accessibility Why are some web sites difficult to use? Many current websites use design, text, images, graphics and scripts in ways that make it difficult to use – this makes them “inaccessible”: • • • no text alternatives for information presented via pictures, audio files, etc. – a screen reader is unable to describe the image use of absolute rather than relative sizing of fonts – prevents users from resizing text to a larger size using colour-only elements to convey information – users with color blindness cannot access information web forms requiring the use of a mouse for navigation – prevents users from using a keyboard web pages that require scripts in order to work – people that have scripting disabled will have difficulties
Web Accessibility How do we determine if a page is accessible? A set of guidelines exist called the Web Content Accessibility Guidelines; published by W 3 C: • Priority 1 (16 checkpoints) = “must” (will be completely inaccessible to some users if not met) – provide a text equivalent for every non-text element eg. images, symbols, animations – for data tables, add row and column headers – provide an auditory description of the visual track of a multimedia presentation • Priority 2 (30 checkpoints) = “should” (will be very difficult to access by some users if not met) – foreground and background should provide sufficient contrast – clearly identify the target of each link – provide a site map or table of contents • Priority 3 (19 checkpoints) = “may” (will be slightly difficult to access by some users if not met) – expand each abbreviation or acronym where it first occurs – enable different types of searches for skill levels and preferences
Web Accessibility Putting it into practice (Demonstration of making an accessible web page for the CW)
JAWS Demonstration of screen-reader software (JAWS) JAWS Software link - http: //www. freedomscientific. com/fs_products/software_jaws. asp • • Good – http: //www. unisa. edu. au Interesting - http: //www. transport. sa. gov. au/index. asp
Questions? Further Information • • • Web Content Accessibility Guidelines – http: //www. w 3. org/TR/WCAG 10/ Uni. SA Online Accessibility Action Plan – http: //www. unisa. edu. au/footer/accessibility/actionplan/default. asp How to make accessible content with Frontpage – http: //www. webaim. org/techniques/frontpage/ Corporate Web Metadata Help – http: //www. unisa. edu. au/wag/construct/metadata. asp Web Authoring Guide – http: //www. unisa. edu. au/wag/ Bobby Test – http: //webxact. watchfire. com/
Скачать презентацию Search Engines Metadata and Accessibility How to make
20e7e56a503e6dd62584de6025be10da.ppt