Information Technology Flashcards
What is a central processing unit (CPU)?
The main component of computer hardware – includes (a) primary storage, (b) a control unit, and (c) an arithmetic/logic unit
What is the primary storage of a CPU?
The part which holds the program, data, and results during processing (and thus involves only temporary storage)
Divided between RAM (random-access memory) and ROM (read-only memory)
What is the control unit of a CPU?
The part which directs the computer’s operations
What is the arithmetic/logic unit of a CPU?
The part with special capabilities to do arithmetic calculations and logical operations
As regards computers, what is a bus?
A communication system for transferring data inside a computer or between computers
What is magnetic tape?
Thin magnetic tape on which data can be imprinted as magnetized dots (e.g. magnetic strips on credit cards)
What is a redundant array of independent disks (RAID)?
A collection of disks that all have the same data written on it – good for backup purposes, but often unnecessary
What is the difference between randomly accessible data and sequentially accessible data?
Randomly = records can be directly accessed
Sequentially = records can be accessed only by reading through previous info
How does software differ from hardware?
Hardware refers to the required physical devices, while software refers to the internal programming and data needed to run the technology
What are the five generations of programming languages?
(1) machine language – simple binary
(2) assembly language – includes short commands for repetitive tasks
(3) procedural language – closer to human language; source code in procedural language can be translated into machine-readable object code
(4) fourth-generation language (4GL) – many routine procedures are preprogrammed
(5) object-oriented programming (OOP) – has a modular approach; focused on the objective rather than the procedure
(3)-(5) are machine-independent
What are some examples of procedural language?
(i) FORTRAN – Formula Translation
(ii) COBOL – Common Business-Oriented Language
(iii) BASIC – Beginners All-Purpose Symbolic Instruction Code
What are some examples of object-oriented programming (OOP)?
(i) C++
(ii) Java
What is a graphical user interface (GUI)?
A display where users can interact with icons, scroll bars, etc. rather than just line-by-line commands
What is a patch?
An additional part added to a program, usually to update it and/or correct a problem
What is an operating system (OS)?
Software that coordinates various computer functions and applications/programs
Also provides a graphical user interface (GUI)
What are some examples of operating systems?
(1) Windows XP
(2) Unix
(3) Linux – a modified version of Unix
What is a job control language (JCL)?
A language used by an OS to do its work
What are multiprocessing and multiprogramming?
Multiprocessing – uses more than one CPU to run more than one program simultaneously
Multiprogramming – a program processes until it needs an input or delivers an output, at which point the OS switches to another program instantly
What is virtual storage?
Occurs when an OS subdivides programs into “pages” and only uses the needed pages to execute the instructions it’s trying to carry out – thus lowers processing costs
What are application programs?
Programs designed to process a particular application
As regards application programs, what is a “pass” or a “run”?
A full round done by the program – input, processing, and output
What are collaborative computing applications?
Any applications where multiple people have access and where the changes made by different people can be tracked to them
What are management information systems (MIS)?
Systems used in a company to provide management with the data it needs
What is enterprise resource planning (ERP)?
A software arrangement that addresses the enterprise’s needs (including financial reporting, inventory management, etc.), seeking to meet the organizational goals by tightly integrating all functions of an enterprise
What is a database management system (DBMS)?
Any set of programs which manages a database, whether by creating it, maintaining it, updating it, allowing access to it, etc.
What is a relational database model?
A model that seeks to relate common data (e.g. customer info) in one integrated database to meet the needs of different users accessing the data
What are utility programs and library programs?
(1) utility programs = programs which perform standard/routine functions, such as merging or sorting
(2) library programs = programs often utilized by other programs, being stored and then “called up” when needed (e.g. random number generation)
Can also be called utility routines or library routines
What is a network?
An arrangement where multiple computers and multiple users have access to common hardware, software, or data
What are an internet, an intranet, and an extranet?
(1) internet = a network of networks (with the internet being a public network of networks)
(2) intranet = a network closed off, usually just to employees
(3) extranet = an internet that is not entirely closed off, but password-protected
What are different kinds of networks?
(1) local area network (LAN) = an intranet within a relatively small physical area
(2) wide area network (WAN) = a network across a very large areas, e.g. a city or country
(3) value-added network (VAN) = a network which provides services beyond Internet capabilities (usually EDI-related)
(4) virtual private network (VPN) = a network where it appears that a remote user accesses a private network, even though it is through public lines
What is a concentrator?
An apparatus which concentrates several communication channels into one
What is a multiplexer?
An apparatus that, for communication purpsoes, converts multiple low-speed transmissions into one high-speed transmission and then back
What is a proxy server?
A server acting as an intermediary for requests from clients involving info from other servers
What is a router?
An apparatus that transfers packets of data outward using the most efficient route possible
What is a firewall?
Software separating segments with the aim of prohibiting anyone from gaining unwarranted access
What is a gateway?
Any software or hardware linking computer networks together
What is a web crawler?
A program that searches the internet to find files for the user
What is topology?
A network’s physical arrangement
Different kinds are (i) bus, (ii) ring, (iii) tree, and (iv) star arrangements
As regards topology, what is a bus arrangement?
Resembles the arrangement of people on a bus: there is one central line (the “bus aisle”) to which several computers are connected
Easy to add more computers with this arrangement, but communication can be cut off by a failed device in the middle
As regards topology, what is a ring arrangement?
Each computer is connected to one on each side, such that all effectively form a circle
Easy to add more computers with this arrangement, and a failed device does not cut off communication (failed devices on each side would), though communication can be slower
As regards topology, what is a tree arrangement?
A hierarchical arrangement where each device can have a number of other devices connected to it as branches
As regards topology, what is a star arrangement?
Each computer is connected to a central device
Generally the most expensive topology
What are data transmission protocols?
Sets of procedures/rules governing the transferal of data among devices
What is the difference between serial and parallel data transmission?
Serial = each bit (of a byte) are transmitted singularly
Parallel = all bits are transmitted simultaneously on parallel lines, one bit per line
Parallel is practicable only with short network distances
What is the difference between circuit switching and packet switching?
Switching mechanisms route bits to take different paths
- circuit switching sends a message in its entirety through oen path
- packet switching sends messages in packets, sometimes through separate paths
What is a common example of packet switching?
TCP/IP – transmission control protocol/internal protocol
Provides protocols for internet packing switching
What is bandwidth?
The degree to which a channel can handle data transmission
Narrow bandwidth signifies a low rate of transmission; broad bandwidth a high rate
What is client-server architecture?
An arrangement where computers on a network are either clients or servers
- clients are workstations or PCs
- servers are powerful machines which can manage networks, disk drives, etc.
As regards client-server architecture, what is the difference between a file server and a database server?
File = the server primarily stores files and processes data; used as the only server in a two-tier client-server architecture arrangement
Database = the server primarily stores software for database management; does some processing
What is a three-tier (or more) client-server architecture?
Any arrangement where two or more servers are needed
The other ones can be print servers, web servers, application servers, fax servers, and so on
What are some different network languages?
(1) hypertext markup language (HTML) – used for internet display
(2) hypertext transfer protocol (HTTP) – protocols governing the coding, transferal, and viewing of data
(3) extensible markup language (XML) – also used for internet display, but further identifies the nature of the info displayed (e.g. phone #s)
(4) extensible business reporting language (XBRL) – required by the SEC, helpful for reading financial statements
What is an internet protocol (IP) number?
A specific number used to identify a particular computer within a network
What does URL stand for?
Uniform resource locator