BTEC theory

BTEC theory

1. Unintended consequences

   • Reputation:The general impression of a person held by others and the public
   • Persist: To continue and endure
   • Context: Different factors that surround a piece of information
   • Tag: To add a descriptive word, label or phrase.

2. World Wide Web

3. The Internet

4. Network Topologies

5. Data Storage

   • Data storage is the storage of information on computers and similar devices.
   • A table is a set of facts or figures systematically displayed, especially in columns
   • A record is a row of data in a table
   • A field is an area in a fixed or known location in a unit of data
   • A relationship is multiple tables linked together
   • A data type is a particular kind of data item, as defined by the values it can take, the programming language used, or the operations that can be performed on it.
   • The primary key constraint uniquely identifies each record in a database table.

6. Data Exchange

7. Computer Networks

   • A computer network is a collection of computers that have been linked together so that they can communicate with each other
   • Computers in a network are joined together by cables or radio waves
   • Computers that are located in the same building or fairly close together are usually connected to form a local area network(LAN).
   • Computers that are a long distance apart, in a different town or country are networked to form a wide area network (WAN).
   • A hardware is a powerful computer that can store many files or programs.
   • In order to log onto a computer network, you need a username and a password.
   • A single computer on a network is known as a work station.
   • Pro's and Con's
     • Sharing devices such as printers saves money.
     • Files can easily be shared between users.
     • Data is easy to backup as all the data is stored on the file server.
     • Security is good - users cannot see other users' files unlike on stand-alone machines.
     • Site (software) licences are likely to be cheaper than buying several standalone licences.
     • Purchasing the network cabling and file servers can be expensive.
     • Managing a large network is complicated, requires training and a network manager usually needs to be employed.
     • Viruses can spread to other computers throughout a computer network.
     • There is a danger of hacking, particularly with wide area networks.
     • Security procedures are needed to prevent such abuse, eg a firewall.