IT_Chapter_1

The Computer Defined

• Electronic device

• Processes data

• Converts data into information

• Modern computers are digital

– Work by the numbers

– Two digits combine to make data

• Older computers were analog

– A range of values made data

Generation of Computers

The development of computers was characterized by phases of growth, which have come to be called as Computer Generations.

First Generation

• 1940 -1956

• vacuum tubes

• huge size – take up entire room

• very expensive

• use lot of electricity

• generated a lot of heat

Second Generation

• 1956-1963

• Transistors

• computers become smaller, faster, cheaper, more energy-efficient and more reliable

• Still generated a great deal of heat

Third Generation

• 1964-1971

• Integrated Circuits

• smaller and cheaper

• increased the speed and efficiency of computers

Fourth Generation

• 1971-Present

• Microprocessors

• VSLI (Very Large Scale Integration): thousands of transistors could be placed on a single chip

• Smallest & cheapest

Fifth Generation

• Present and Beyond

• Artificial Intelligence

• Goal - to develop devices that respond to natural language input and are capable of learning and self-organization

• voice recognition, robotics

Computers For Individual Use

• Used by only one person at a time

• PC or Microcomputers

• Six primary types

1. Desktop computers

2. Workstations

3. Notebook computers

4. Tablet computers

5. Handheld computers

6. Smart phones

• Desktop computers

– The most common type of computer

– Sits on the desk or floor

– Performs a variety of tasks

– System Unit (vertical/horizontal)

• Workstations

– Specialized computers

– Optimized for science or graphics

– More powerful than a desktop

• Notebook computers

– Small portable computers

– Typically as powerful as a desktop

– Mobile computers

• Tablet computers

– Newest development in portable computers

– Input is through
a pen (stylus)

– Run specialized versions of office products

• Handheld computers

– Very small computers

– Personal Digital Assistants (PDA)

– Note taking or contact management

– Data can synchronize with a desktop

• Smart phones

– Hybrid of cell phone and PDA

– Web surfing, e-mail access

Computers For Organizations

• Handle the needs of many users at the same time

• Can support thousands of individual users at the same time, from thousands of miles away

• Network servers

– Centralized computer

– All other computers connect

– Provides access to network resources

– Multiple servers are called server farms

– Often simply a powerful desktop

• Mainframes

– Used in large organizations

– Handle thousands
of users

– Users access through a terminal

– Dumb & Intelligent terminal

– banks., insurance companies

• Minicomputers

– Called midrange computers

– Power between mainframe and desktop

– Handle hundreds of users

– Used in smaller organizations

– Users access through a terminal

• Supercomputers

– The most powerful computers made

– Handle large and complex calculations

– Process trillions of operations per second

– Found in research organizations

Computers In Society

• More impact than any other invention

– Changed work and leisure activities

– Used by all demographic groups

• Computers are important because:

– Provide information to users

– Information is critical to our society

– Managing information is difficult

• Computers at home

– Many homes have multiple computers

– Most American homes have Internet

– Computers are used for

• Business

• Entertainment

• Communication

• Education

• Computers in education

– Computer literacy required at all levels

• Computers in small business

– Makes businesses more profitable

– Allows owners to manage

• Computers in industry

– Computers are used to design products

– Assembly lines are automated

• Computers in government

– Necessary to track data for population

• Police officers

• Tax calculation and collection

– Governments were the first computer users

• Computers in health care

– Revolutionized health care

– New treatments possible

– Scheduling of patients has improved

– Delivery of medicine is safer