Unit 3 Computer

ii. television
old portable television
a television (also tv or telly) is a device (tool) with a screen that receives broadcast signals and turns them into pictures and sound. the word “television” comes from the words tele (greek for far away) and vision (seeing).
usually a tv looks like a box. older tvs had large wooden frames and sat on the floor like furniture. newer tvs became smaller so they could fit on shelves, or even portable so you could take it with you wherever you went. the smallest tvs can fit in your hand. the largest tvs can take up a whole wall in your house, and may sit on the floor, or be just a large flat screen that can be mounted on the wall. many tvs are now made in wide screen shape like movie theatre screens, rather than old, more square tvs.
a television has an antenna (or aerial), or it has a cable. this gets the signal from the air, or cable provider. tvs can also show movies from dvd players or vcrs. tvs can be connected to computers and game consoles, usually through a kind of socket called “scart”.
iii. web or world wide web
the world wide web is the part of the internet that contains web sites and web pages.
it is not used to describe webpages that are used offline where net services are not available, or no computer network exists - such as wikipedia on cd. in this case no real physical site exists other than the place where the computer is. blog and wiki capabilities will also not be available because these require a communication with other computers.
iv. radio
radio is a communications invention. though originally used to communicate between two people, it is now used to listen to music, news, and people talking. radio shows were the predecessor to tv programs.
v. dvd
dvd most commonly stands for “digital versatile disk”. it can play video that is of a higher quality than a vhs tape.
vi. two kinds of dvd
they can also hold 4.7 gb of information as opposed to the 700 mb that a cd can hold. a plus of using a dvd for a video is the ability to have interactive menus and bonus features such as deleted scenes and commentaries.
vii. email
email (electronic mail) is a message, usually text, sent from one internet user to another. email is quicker than snail mail(mail) when sending over long distances and is usually free. to send or receive an email, a computer with a modem and telephone line connected to the internet, and an email program are required. email addresses are generally formated like this: login@server.(com or fr or org or uk or other).