Internet Browser

The syllabus refers to: used to access a machine independent data store.

This means the data store is not dependent on the type of software that the computer runs on.

Software for retrieving data from the Web

A web browser allowsyou to retrieve data stored on a web server and display it on your computer monitor or screen. The data retrieved from the web server must be independent of the computer you are using. This means that the data displayed on your computer screen should be the same no matter what type of computer you have or what operating system you are using.
A web browser is a software application that builds a web page on your display from the data contained in a HTML document/ Browsers must be able to perform a wide range of data retrieval and formatting tasks to construct a web page. The images show in a page may not all come from the same web server.

Software for storing data on the Web

Software need to create a web page can be quite simple. Web pages, the images and any other data they contain, are stored on Internet computers, generally known as 'web servers'. Web servers are where your browser collects data to display a web page, and where web page information is stored.

Search Engines

The term search engine is often used to describe a web site that gives you a list of web pages that match your entered search request. A web search request is an instruction to find entries in the database. The databases used by search engines will probably be the largest and most sophisticated you will ever use.
Most search engines fall into one of two categories:

  • True search engines use automated software agents to search the web for new pages and to recheck those they have previously found. This process if often called 'crawling' and the software agent is called a 'crawler' or 'spider'. The crawling creates a list of web pages, their addresses and basic information about them.
  • Web directories are created entirely by humans. You have to submit the details of your web site to human editors at the directory service. They then decide, based on your description and perhaps a site inspection, how to classify your site in their directory system. Web directories let you navigate your way to locate pages on a particular subject. Most will also have a search engine to do this navigating for you.