Transcript Internet
Internet Standard Grade Computing Internet • a wide area network spanning the globe. • consists of many smaller networks linked together. Service • a way of using the internet to perform specific tasks Services available on the Internet Three main services: World Wide Web gives access to information in remote computers through browsing or searching Email messages between computers File transfer to send or receive large files Other services Chat a web site where users can take part in text discussions with other users Instant messaging a program that looks for your friends online and tells you that they can receive messages Bulletin boards (forums) an electronic notice board where users can post, read, look at messages Discussion group geographically separated users with a common interest hosted on a web site Web logs a web page made up of short entries in chronological (time) order like a diary On-line banking On-line shopping Video streaming the process of receiving video images over a network and displaying them on a computer screen Video Conferencing uses communication links to conduct meetings between people who are geographically separated. Requires a computer system and a webcam in each location together with a network connection To connect to the Internet you need: computer system modem communications software eg. browser and email client program Internet Service Provider (ISP) Internet Service Provider (ISP) A company that provides a host computer connected to the Internet which the user can access. The host computer manages communications and stores data such as email and web pages Modem a piece of hardware that changes the digital signals from a computer into “telephone signals” which can be sent along a normal telephone line. A modem at the other end changes the signals back into digital form for the receiving computer. Internet ready computer – consists of: • computer system • internal modem • communications software eg. browser and email client program Mobile Internet Technologies Includes palmtops, laptops, mobile phones. Do not need a mains power supply or physical connection to the Internet, which can be achieved using wireless networking interface cards. Dial-up connection a wire connects the computer’s modem socket to the telephone socket. The communication software dials the ISP’s number and establishes a connection to the Internet. Broadband connection constantly connected to the Internet, much faster access. Telephone can be used at same time. More than one computer can be connected to Internet at same time. Another definition of online… Online – connected to the Internet. Offline – disconnected. Downloading Software Downloading Receiving a file from a network (server or individual computer) and saving it onto a computer system. Freeware Totally free software that can be used on any number of computer systems. Downloading Software Shareware Free for a short trial period to let you try it. After that you must either delete the software or pay to continue using it. Some crucial functions usually missing (e.g. save, print). Commercial software Must be paid for. Can only be used on one computer without a special license. You cannot legally make copies. World Wide Web Browser • a program that allows the user to access web pages (surf the net) eg. Internet Explorer Web page • a single document or file on the World Wide Web • identified by a unique URL (Universal Resource Locator) • can used to hold information in multimedia form World Wide Web Hyperlink Links Web pages, documents or files; activated by clicking with the mouse. HTML Hypertext mark-up language. A special language used to create Web pages. Search Engine A site designed to help you find information. The user can enter keywords. Simple Search The user enters one or more keywords Complex Search Allows the user to refine a search by restricting the search to only parts of the Web. Most allow the use of AND ( +), OR, NOT ( - ) eg. mountain + scotland The Big Bad World Wide Web Is inhabited by? Who controls it? Who checks the information is correct? Who has access •to the WWW? •to your data on the WWW? Creating a web page Simplest way is to use • a wizard or • a template You can then • enter your text • add graphics Creating a better web page To create a more interesting page, add • audio • video • hyperlinks using text or hotspots (A defined area in a graphic containing a hyperlink) Present information using tables Internet Standard Grade Computing End of presentation