Information Technology in Financial Services : Introduction to Computer

BANKING DIPLOMA EXAMINATION

Banking Diploma Courses under The Institute of Bankers, Bangladesh (IBB)

Information Technology in Financial Services-DAIBB
Introduction to Computer

Definition of computer:

In general terms, a computer is an electronic device used to process data, converting the data into information that is useful to the people.

A programmable machine. The two principal characteristics of a computer are:

§  It responds to a specific set of instructions in a well-defined manner.

§  It can execute a prerecorded list of instructions (a program).

Modern computers are electronic and digital. The actual machinery -- wires, transistors, and circuits -- is called hardware; the instructions and data are called software.

Computer system:

A complete computer system consists of four parts: Hardware, software, people and data.

Hardware: the mechanical devices that makeup the computer are called hardware, in other words part of the computer you can touch.

All general-purpose computers require the following hardware components:

  Memory : Enables a computer to store, at least temporarily, data and programs.

  Mass Storage Device : Allows a computer to permanently retain large amounts of data. Common mass storage devices include disk drives and tape drives.

  Input Device : Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer.

  Output Device : A display screen, printer, or other device that lets you see what the computer has accomplished.

  Central Processing Unit (CPU): The heart of the computer, this is the component that actually executes instructions

Software:  software is a electronic instruction consisting of complex codes (also known as programs) that make the computer perform its tasks. Other words software tells the computer what to do.

Computer users (people): people are the computer operators also known as users.

Data: data consists of raw facts, which the computer stores and reads in the form of numbers. The computer manipulates data according to the instruction contained in the software and then forwards it for use by people or another computer.

What is file and documents? (Prepare answer yourself)

Classification of computer system:

·         By Generation

·         By type.

By type: Today’s computer systems fall into one of the following categories regarding their types:

ü  Supercomputer

ü  Mainframe computer

ü  Minicomputer or midrange computers

ü  Workstations

ü  Microcomputers or personal computer

Supercomputers: super computer are the most powerful computers made, and physically they are some of the largest these systems are built to process huge amount of data, a typical supercomputer can perform more than I trillion calculation per second.

Application of Supercomputer:

Ø  These computers help analyze and forecast global whether patterns

Ø  Nuclear scientists use supercomputers to crate and analyze models of nuclear fusion and fission.

Ø   They are also being used to map the human genome or DNA structure.

Supercomputers can cost tens of millions of dollars and consume very high electricity. Because of their large size, and cost supercomputers are relatively rare and used only by large corporation, Universities and government agencies that can afford them.

Mainframe computers: The largest type of computer in common use is the mainframe. A mainframe computer can house an enormous amount of data, containing literally billions of records. Large mainframe system can handle the input and output requirement of several thousand terminals. The largest IBM/390 mainframe, for example can support 50,000 users simultaneously while executing more than 1600000000 instructions per second.

 Applications of Mainframe:

ü  They are used in large organization like insurance companies and banks where many need frequent access to the same data, which is organized into one of more huge data bases.

ü  Airline uses large mainframe system for flight scheduling, reservation, ticketing and meeting a range of customer service needs.

ü  Government agencies uses mainframe to track information about large populations individual tax recodes, payroll and more.

Minicomputer: First released in the 1960s, minicomputer got their name because of their small size compared t other computer of the day. They are also called midrange computers. Like mainframe minicomputers can handle much more input and output than personal computers can. The most powerful minicomputers can serve the input and output seed of hundreds of users at a time.

Applications of minicomputers:

ü  They ate commonly used as servers in network environments that handle the data-sharing needs of other computers on the network.

Workstations: Somewhere between multi-users midrange computer and personal computers are workstations. They are specialized, single user computers with many of the features of  a personal computer but with the processing power of a minicomputer. They typically use advanced processors and feature more RAM and storage capacity than personal computers.

Applications:

ü  This powerful machines are popular among scientist, engineers, graphic artist, animators and programmers.

Microcomputer or Personal computer:  there are two major families of Personal computer

ü  IBMs and IBM-compatible.

ü  Apple Macintosh.

IBMs and IBM-compatible: In 1981 IBM called its first microcomputer the IBM-PC . within a few years many companies were copying the IBM design, creating the clones or compatibles that were meant to function like original. Today they are most widely used microcomputer.

Apple Macintosh:  The apple Macintosh how ever is neither an IBM nor a compatible. Ti is another family of microcomputer. They uses Apples proprietary OS which is design for simplicity of use. 

One source of the PC’s popularity is the rate at which improvements are made is its technology. Microprocessors, memory chips, and storage devices make continual gain in speed and capacity.

The microcomputer category has grown tremendously in the past decade. They are giver below:

Ø  Desktop model including tower models.

Ø  Notebook computer also called laptop computers

Ø  Network computers

Ø  Handheld personal computers of all types.

Desktop model including tower models:  traditionally a desktop computers system unit is horizontally oriented meaning it can lie flat on a desk of table.

In a tower model the system unit sits vertically and provide more space for other devices. It has become increasingly popular in recent years.

Notebook computer also called laptop computers:

This type of computer as their name implies, app. The shape of an 8.5 by11 inch notebook weighing around 2 kg and can fit inside a briefcase easily. Also called Laptop computer. They can operate on alternating current or special batteries. Because of their size reduction they tend to be more expensive than comparably equipped desktop computers.

Network computers : 

In some cases, a user does not need all the power and feature provided by a personal computer. If you want to use only the internet or your jobs involves data entry only then you may not need the processing power, memory of a fully equipped PC. In this instance a network computer becomes useful.

Network computers are design to be connected to a network or to the internet. The NC relies on the network for software and data storage and may even use networks server to perform processing tasks.

In home setting some NC do not even include a monitor, instead they connect to the users television, which servers as the output devices. A popular example of home based NC is Web TV, which enables the users to connect a television to the internet and enjoy both standard television programming and Internet services. The Web  TV used a special set-top Box to connect to the internet.

I

n corporate setting, NC’s such as Sun JavaStation, offers several other advantages:

ü  Enhanced data security

ü  Reduced threat of virus

ü  Centralized software

ü  Limited upgrades.

Handheld Personal computer:

This tiny systems ate also called Palmtop computers. A handheld computers can be any sort of computer that fits in the users hand such as

Ø  Personal digital assistance (PDA)

Ø  Cellular telephone with internet, e-mail. And fax capabilities.

Ø  H/PC Pro devices

Personal Digital Computers:  they are among the smallest of portable computers. They are normally used for special applications such as taking notes displaying telephone numbers, and addresses and keeping track of dates and agendas.

PDAs may include the following features:

ü  User can write on a touch sensitive screen. It uses built in microphone and speaker enabling the user to record speech digitally.

ü  Personal information management software.

ü  Miniaturized versions of personal productivity applications.

ü  Internet, fax or e-mail, software.

Cellular Phone:  some advanced cellular devices provides the users to send e-mail and faxes over the phone. They offer the feature not normally found on a phone, such as personal organizer or access t the Web.  

H/PC Pro devices: these systems are larger than PDA’s but they are not quite as large as typical note book PC’s. they include the following features

• H/PC Pro boast the full-size keyboard and color displays.
• They offer long batteries and instant on access
• They do not include disks. Although thy will gain speed and storage capacity quickly H/PC Pro system offers very limiter RAM and relatively slower processor speeds.

Generation of Computers

First generation of computers (1937-1953):

The first electronic computer was completed in 1946 by a team led by professor Eckert and Mauchly at the University of Pennsylvania in USA. This computer is called Electronics numerical Integrator and calculator (ENIAC). Some features of  the first generation computer is given below.

• It had very small memory and primarily design to calculate the trajectories of missiles. It took about 200 microsecond to add two digit and about 2800 microseconds to multiply. 
• They used high speed vacuum tube switching devices. Filament used by vacuum tube had limited life time. They also consume half a watt power.
• Programming was mainly done in machine language. The concept of operating system had not been emerged.

Second generation of computers (1954-1962):

A big revolution took place with the invention on transistor by Bardeen, Brattain and Shockly in 1947. transistors made of germanium semiconductor material were highly reliable compared to the tubes since it had no filament to burn. Some features of this generation are given below:

• The switching ckt for computers made with transistors were about ten rime times more reliable, ten time faster, consume one tenth the power, occupied about one tenth the space and were ten times cheaper than those using tubes.
• Invention of magnetic core for storage. This magnetic core were used to construct large random access memory (100 Kilo byres)
• Operating system were developed. Good operating system, particularly the one on IBM 7000 series computer emerged during second generation.
• High level programming languages were developed.

Third generation of computers (1963-1972):

In this generation germanium transistors being replaced by silicon transistors. Integrated ckts consisting of  transistor, resistor and capacitors grown on single chip of silicon eliminating wired interconnections between components. Some features are given below:

• Technology had developed from SSI (10 transistors per chip) ckt to MSI (100 TPC).
• Switching speed and reliability went up by a factor of 10 and size and power dissipation were reduced by a factor of 10.
• There were significant development on magnetic core memory (4Megabytes) 
• Time shared operating system were developed. 
• Many important on-line system become feasible, and high level languages were improved. FORTRAN IV and COBOL. 
• Computer designers began to take advantage of parallelism by using multiple functional units, overlapping CPU and I/O operations, and pipe lining (internal parallelism) in both the instruction stream and the data strea

Fourth generation of computers (first phase, (1975-85)

 The fourth generation may be identified by the advent of the microprocessor chip. Marcian Hoff invented a device which could replace several of the components of earlier computers, the microprocessor. The microprocessor is the characteristic of fourth generation computers, capable of performing all of the functions of a computer's central processing unit. The reduced size, reduced cost, and increased speed of the microprocessor led to the creation of the first personal computers. Some features are given below:

• MSI ckts yielded to LSI and VLSI ckts packing about 50000 transistors in a chip. 
• Magnetic core memory were replaced by semiconductor memories. (16megabytes with 200 nanoseconds of cycle time), disk memory became very large(1000 Mbytes)
• Network of computers and distributed computer system were developed. 
• This generation saw thi coming of age of UNIX OS and time shared interactive system. This system become user friendly and highly reliable. 

Fourth generation of computers (second phase, 1986-1998):

The second phase of the fourth generation has seen a relentless in the speed of microprocessor and the size of the maim memory. The speed of microprocessor and the size of main memory and hard disk went up by a factor of 4 every 3 years.

• Microprocessor such as Pentium, power PC etc are being used as the CPU of personal computer and portable laptop and palm held computers. 
• The area oh hard disk storage also saw a vast improvement. 1 GB of disk on workstation become common in 1994. Optical disk(CD ROM and DVD (digital versatile disk) ROM ) also emerged as mass storage device. Writable CD were also introduced.
• Rapid increase in the number of computers connected to the internet. This led to the emergence of the world wide web which ease information retrieval.
• Object oriented programming languages like C,C++, JAVA were developed.