Once a function is defined, it can be used over and over and over again. Reusability of a single function several times is known as an abstraction.

In iteration, the loop body is repeatedly executed as long as the loop condition is true. Each time the loop body is executed, the variables are updated.
However, there is also a property of the variables which remains unchanged by the execution of the loop body. This unchanging property is called the loop invariant.

Open source refers to a program or software in which the source code is available in the web to all public, without any cost.

(i) BCD - Binary Coded Decimal.
(ii) EBCDIC - Extended Binary Coded Decimal Interchange Code.
(iii) ASCII - American Standard Code for Information Interchange
(iv) Unicode.
(v) ISCII - Indian Standard Code for Information Interchange

A Multi-user Operating system is a computer operating system (OS) that allows multiple users on different computers or terminals to access a single system with one OS on it.

Ultra violet rays are used to erase the contents of EPROM. EPROM retains its contents until it is exposed to ultraviolet light. The ultraviolet light clears its contents making it possible to reprogram the memory.

Data Information Data is a collection of facts from which the information may be derived. It is an unprocessed collection of facts in a manner suitable for communication, interpretation or processing. Information is a collection of facts from the conclusions can be drawn. Information is a processed facts, active, Business based and transformed from data. Eg. 134, 16, Kavitha Does not give meaning. Eg. Kavitha is 16 years old.
Conveys meaning.

Assignment Operator	Equality Operator
Assignment operator is used to assign the values to the variable.	The equality operator is used to compare the values of both the variables and the result is true or false.

Change it to Binary

150₁₀ = 10010110₂
Step 2 : Change it to Octal
10,010,110
421 421 421
010 010 110
Binary 10010110₂
Octal =226₈

Uses of Cortana:
1. Cortana is a voice activated personal assistant.
2. Give the reminders based on time, places, or people.
3. Track packages, teams, interests, and flights.
4. Send emails and texts.
5. Manage the calendar and keeps up to date.
6. Create and manage lists.
7. Chit chat and play games.
8. Find facts, files, places, and info.
9. Open any app on the system.

PROM	EPROM
Can be Programmed only once.	It is reusable and can be programmed multiple times.
This has Permanent memory.	EPROMs memory can be erased using UV light.
Enclosed in plastic package so that not visible to UV light.	EPROMs are fused with quartz window.
Uses high Voltage.	Also use high Voltage but not enough to alter the semiconductor layer permanently.

Advantages and disadvantages of Time Sharing Option (TSO)

Time-Sharing Operating Systems
Advantages	Disadvantages
Each task and each user get its time.	Problem in Reliability
Systems have to give time to these application individual tasks and other applications also, so that all system behave correctly.	It consumes many resources so it need special operating systems.
Reduces the CPU ideal time	Need High specification hardware

Optical Mouse	Laser Mouse
It is less sensitive towards the surface	Highly sensitive
Tracking power is less	Tracking power is more
Old technology	Latest technology
This uses the light source instead of ball to judge the motion of the pointer.	This uses Laser light
Optical mouse has 3 buttons	No. of buttons will vary from 3 to many

(a) Inkjet Printer:
(i) Inkjet printer use colour cartridges which combined magenta, yellow and cyan inks to create colour tones.
(ii) A black cartridge is used for monochrome output. Inkjet printer works by spraying ionised ink at a sheet of paper.
(iii) The speed of inkjet printers generally range from 1-20 ppm (page per minute)
(iv) An inkjet printer can spread millions of dots of ink at the paper every single second.
(v) They use the technology of firing ink by heating it so that it explodes towards the paper in bubbles or by using piezo electricity in which tiny electric currents are controlled by electronic circuits.
(b) Multimedia Projector:
(i) Multimedia projectors are used to produce computer output on a big screen.
(ii) These are used to display presentations in meeting halls or in class rooms.
(c) Barcode/ QR code Reader:
(i) A Bar code is a pattern printed in lines of different thickness.
(ii) The Bar code reader scans the information on the bar codes transmits to the computer for further processing.
(iii) The system gives fast and error free entry of information into the computer.
Quick response (QR) code:
The QR code is the two dimension bar code which can be read by a camera and processed to interpret the image.

98.46₁₀

2. Fractional part
0.46 x 2 = 0.92 = 0
0.92 x 2 = 1.84 = 1
0.84 x 2 = 1.68 = 1
0.68 x 2 = 1.36 = 1
0.36 x 2 = 0.72 = 0
0.72 x 2 = 1.44 = 1
98.46₁₀ = (1100010.011101...)₂

The benefits of open source are tremendous and have gained huge popularity in the IT field in recent years. They are as follows:
1. Open source (OS) is free to use, distribute and modify.
2. Open source is independent of the company as author who originally created it.
3. It is accessible to everyone. Anyone can debug the coding.
4. It doesn't have the problem of incompatible formats that exists in proprietary software.
5. It is easy to customize as per our needs.
6. Excellent support will be provided by programmers who will assist in making solutions. Some of the disadvantages are:
7. Latest hardware are incompatible, i.e. lack of device drivers.
8. It is less user friendly and not as easy to use.
9. There may be some indirect costs involved such as paying for external support.
10. Malicious users can potentially view it and exploit any vulnerability.

(a) Clock speed-Each microprocessor has an internal clock that regulates the speed at which it executes instructions. The speed at which the microprocessor executes instructions is called clock speed. It is measured in MHz vi in GHz.
(b) Instructions set - The set of machine level instructions that a microprocessor is designed to execute is called as an instruction set. This carries 4 types of operations. They are
1. Data transfer
2. Arithmetic operations
3. Logical Operations
4. Control flow
5. Input/output
(c) Word size - The number of bits that can be processed by a processor in a single instruction is called as its word size. It determines the amount of RAM that can be accessed at one time and the total number of pins on the microprocessor. Total number of input and output pins in turn determines the architecture of the microprocessor.