These Notes from the class of BS EDUCATION 1st Semester (Spring) Session 2023-2027 Teacher :Ch Naveed Afzal semester started in march 2023 and end in july 2023

1. Classification of Computers According to work
Computer types can be divided into 3 categories according to work.
Analogue Computers
Digital Computers
Hybrid Computers
a. Analog Computers
Analog computers are used to process continuous data. Analog computers represent
variables by physical quantities. Thus any computer which
solve problem by translating physical conditions such as flow,
temperature, pressure, angular position or voltage into related mechanical or electrical related
circuits as an analog for the physical phenomenon being investigated in general it is a computer
which uses an analog quantity and produces analog values as output. Thus an analog computer
measures continuously. Analog computers are very much speedy. They produce their results very
fast. But their results are approximately correct. All the analog computers are special purpose
computers. Example:Mercury thermometer,barometers, etc.
b. Digital Computer type
Digital Computer is a machine specializes in counting. It operates by counting values that
are discrete, or separate and distinct, unlike the
continuous quantities that can be measured by the analog
computer. Digital Computers are used for both business
data processing and accuracy. The basic operation performed by a digital computer is addition. It
can store the sums of addition problems as they accumulate, and can complete a single
calculation in a fraction of a nanosecond. The digital computer is capable of storing data as long
as needed, performing logical operations, editing input data, and printing out the results of its
processing at high speed. Examples: computers, calculators, etc.
c. Hybrid type of Computer
Although both analog and digital computers are extremely used in widely accepted in
various industries, manufacturers have to attempt to design a computer that combines the best
features of both types. This special-purpose machine called a hybrid, computer, combines the
measuring capabilities of the analog computer and the logical and control capabilities of the
digital computer. It offers an efficient and economical method of working out special types of
problems in science and various areas of engineering. Some Hybrid machines contain special
equipment to convert analog voltages into digital voltages, and vice-versa.

2. Name Equal To Size(In Bytes)
Bit 1 Bit 1/8
Nibble 4 Bits 1/2 (rare)
Byte 8 Bits 1
Kilobyte 1024 Bytes 1024
Megabyte 1, 024 Kilobytes 1, 048, 576
Gigabyte 1, 024 Megabytes 1, 073, 741, 824
Terrabyte 1, 024 Gigabytes 1, 099, 511, 627, 776
Petabyte 1, 024 Terabytes 1, 125, 899, 906, 842, 624
Exabyte 1, 024 Petabytes 1, 152, 921, 504, 606, 846, 976
Zettabyte 1, 024 Exabytes 1, 180, 591, 620, 717, 411, 303, 424
Yottabyte 1, 024 Zettabytes 1, 208, 925, 819, 614, 629, 174, 706, 176