2. • A computer can thus be defined as a device that
can perform both arithmetic and non-arithmetic
operations accurately on given data or
information at a high speed.
• The set of instructions, which directs the
computer to produce a desired result, is called a
program. Thus a computer system is essentially
driven by a program
• In technical terms: a computer is a device that is
designed to accept and store input data, process
it and produce desired results under the
direction of the instructions written in the
program.
3. Characteristics of Computers
1. Speed: today the speed is over 80,000 MIPS.
2. Accuracy: All computer systems besides
having amazing speeds have nearly 100%
accuracy.
3. Reliability: Reliability of any computer
system is typically as high as 99.99%.
4. Memory: is the electronic holding place for
data and instructions.
5. Storage: various computer media can hold
billions of bytes of data.
4. Applications of Computers
• Schools: Computer Based Training (CBT)
• Medicine and Hospital administration: storing
medical records of patients for future reference.
• Railways and airlines ticketing: railway and airlines
ticket booking is done entirely through computers
• Banks: ATM (Automatic Teller Machine) and modern
banking system.
• Scientific and engineering applications: designing of
bridges, multi-storied buildings, automobiles etc.
• Business and administrative applications: payroll
processing, inventory control, sales analysis and
forecasting, word processing, census, questionnaire
analysis etc.
5. • Avionics and Space flights: modern aircraft can fly
only with the aid of an onboard computer. Most
modern aircraft have a facility known as autopilot
which can take the control of most of the operations
of a pilot.
• Humanities: used extensively in field such as
archaeological research, music analysis and
composition, graphic art and linguistics.
• Police Work: use computer for maintaining their
records, which make it easier to fight crimes.
• Metrology: use to predict weather, rainfall and
monsoon patterns in the country
• Entertainment: special effects of movies, computer
assisted pictures. Composing, editing etc.
