3rd week: web searching

The 2^nd lecture, we will get to learn about:

ü  Web browser

ü  Search tools

ü  Searching technique

Web browser

Explain in an easier way—software that display web pages, allow user access to WWW

Explain in BLAHBLAHBLAH—software application that enables a user to display and interact with text, images, and other information typically located on a web page at a website on the World Wide Web or a local area network.

Example of 10 common web browsers:

here come 10 of the common web browser~

Don’t forget click on it to enlarge o~~

Even some of the users create a girly version for 

the web browser we usually use ♥

(once again, click to enlarge ya~)

Search tools

Easier version—Software that enables users to search the Internet using keywords.

Full version— help users of the Internet locate information on the World Wide Web. It collects and indexes Internet resources and provides a keyword search system allowing the user to identify and retrieve resources. There are many search engines available and each is different in their scope, search protocols, and appearance.

Search engine do :

1. Searches the database
2. Returns a list of suitable URLs which match your query.
3. Allows user to revise and resubmit
4. Allows user to submit a query that consist a word / phrase

The top 10 search engine for beginner user:

can click on the image, it's a link to that search engine owh~~

<click> wiki for the search engine

 

Search technique

Use key search engines effectively

Use meta-search engines

Use specialty databases when appropriate

Use subject directories

Meaning of.....

Cache

is a component that transparently stores data so that future requests for that data can be served faster. The data that is stored within a cache might be values that have been computed earlier or duplicates of original values that are stored elsewhere. If requested data is contained in the cache (cache hit), this request can be served by simply reading the cache, which is comparatively faster. Otherwise (cache miss), the data has to be recomputed or fetched from its original storage location, which is comparatively slower. Hence, the greater the number of requests that can be served from the cache, the faster the overall system performance becomes.
To be cost efficient and to enable an efficient use of data, caches are relatively small. Nevertheless, caches have proven themselves in many areas of computing because access patterns in typical computer applications have locality of reference. References exhibit temporal locality if data is requested again that has been recently requested already. References exhibit spatial locality if data is requested that is physically stored close to data that has been requested already.

 

URL

A URL is one type of Uniform Resource Identifier (URI); the generic term for all types of names and addresses that refer to objects on the World Wide Web.
The term "Web address" is a synonym for a URL that uses the HTTP / HTTPS protocol.
The Uniform Resource Locator (URL) was developed by Tim Berners-Lee in 1994 and the Internet Engineering Task Force (IETF) URI working group. The URL format is specified in RFC 1738 Uniform Resource Locators (URL).



multitasking
In computing, multitasking is a method where multiple tasks, also known as processes, share common processing resources such as a CPU. In the case of a computer with a single CPU, only one task is said to be running at any point in time, meaning that the CPU is actively executing instructions for that task. Multitasking solves the problem by scheduling which task may be the one running at any given time, and when another waiting task gets a turn. The act of reassigning a CPU from one task to another one is called a context switch. When context switches occur frequently enough the illusion of parallelism is achieved. Even on computers with more than one CPU (called multiprocessormachines), multitasking allows many more tasks to be run than there are CPUs.



metasearch engine


A metasearch engine is a search tool that sends user requests to several other search engines and/or databases and aggregates the results into a single list or displays them according to their source. Metasearch engines enable users to enter search criteria once and access several search engines simultaneously. Metasearch engines operate on the premise that the Web is too large for any one search engine to index it all and that more comprehensive search results can be obtained by combining the results from several search engines. This also may save the user from having to use multiple search engines separately.
The term "metasearch" is frequently used to classify a set of commercial search engines, see the list of search engines, but is also used to describe the paradigm of searching multiple data sources in real time. The National Information Standards Organization (NISO) uses the terms Federated Search and Metasearch interchangeably to describe this web search paradigm.



plug-in


In computing, a plug-in (or plugin) is a set of software components that adds specific abilities to a larger software application. If supported, plug-ins enable customizing the functionality of an application. For example, plug-ins are commonly used in web browsers to play video, scan for viruses, and display new file types. Well-known plug-ins examples include Adobe Flash Player, QuickTime, and Microsoft Silverlight.
Add-on (or addon) in computing is often considered the general term comprising snap-ins, plug-ins, extensions, and themes for software applications.



temp file


Temporary files may be created by computer programs for a variety of purposes; principally when a program cannot allocate enough memory for its tasks, when the program is working on data bigger than the architecture's address space, or as a primitive form of inter-process communication.

By Mhui