S.No	Windows	Ubuntu
1.	Recycle Bin	Trash
2.	My computer	Files
3.	Ms word	Libreoffice writer

The main purpose of using an operating system:
(i) It controls and coordinates all the activities of a computer system.
(ii) It provides an environment for a computer user to execute programs on computer hardware in a convenient and efficient manner.
(iii) It enables the user to design the application, and also it provides an interface to interact with the computer and controls the execution of all kinds .of programs without knowing the internals of the hardware.
(iv) It interprets the command and instructions to perform the specified tasks.
(v) It coordinates and assigns the compilers, assemblers, utility programs to the users.
(vi) It detects errors present in the hardware and software.
(vii) It maintains the internal time clock.
(viii) It protects itself from being destroyed by any users.
(ix) It serves two major functions
1. Supervision (Prevent errors)
2. Management (Operation and control of I/O devices)
(x) It loads the programs itself into memory so that user can interact with hardware and software.

Read only memory (ROM):
(i) Read Only Memory refers to special memory in a computer with pre-recorded data at manufacturing time which cannot be modified. The stored programs that start the computer and perform diagnostics are available in ROMs.
(ii) ROM stores critical programs such as the program that boots the computer. Once the data has been written onto a ROM chip, it cannot be modified or removed and can only be read.
(iii) ROM retains its contents even when the computer is turned off. So, ROM is called as a non-volatile memory
Programmable Read only memory (PROM):
(i) Programmable read only memory is also a non-volatile memory on which data can be written only once. Once a program has been written onto a PROM, it remains there forever.
(ii) Unlike the main memory, PROMs retain their Contents even when the computer is turned off.
(iii) PROM is manufactured as a blank memory, whereas ROM is programmed during the manufacturing process itself. PROM programmer or a PROM burner is used to write data to a PROM chip. The process of programming a PROM is called burning the PROM.
Erasable Programmable Read-only memory (EPROM):
(i) Erasable Programmable Read-Only Memory is a special type of memory which serves as a PROM. The content can be erased using ultraviolet rays.
(ii) An EPROM differs from a PROM. PROM can be written only once and cannot be erased.
(iii) EPROMs are used widely in personal computer, because they enable the manufacturer to change the contents of the PROM to replace with updated versions or erase the contents before the computer is delivered.
Electrically Erasable Programmable Read-Only Memory (EEPROM)
(i) Electrically Erasable Programmable Read-Only Memory can be erased by exposing it to an electrical charge.
(ii) Like other types of PROM, EEPROM retains its contents even when the power is turned off. Comparing with all other types of ROM, EEPROM is slower in performance.

A Microprocessor's performance depends on the following characteristics:
(a) Clock speed
(b) Instruction set
(c) Word size
(a) Clock Speed
(i) Every microprocessor has an internal clock that regulates the speed at which it executes instructions.
(ii) The speed at which the microprocessor executes instructions is called clock speed. Clock speed is measured in MHz (Mega Hertz) or in GHz (Giga Hertz).
(b) Instruction set
(i) A command which is given to a computer to perform an operation on data is called an instruction.
(ii) Basic set of machine-level instructions that a microprocessor is designed to execute is called as an instruction set. This instruction set carries out the following types of operations:
1. Data transfer
2. Arithmetic operations
3. Logical operations
4. Control flow
5. Input/output
(c) Word Size:
(i) The number of bits that can be processed by a processor in a single instruction is called its word size.
(ii) Word size determines the amount of RAM that can be accessed by a microprocessor at one time and the total number of pins on the microprocessor.
(iii) Total number of input and output pins in turn determines the architecture of the microprocessor.

a. 1101010₂ + 101101₂
1101010
+101101
________
10010111
________
1101010₂ + 101101₂ = 10010111₂
b. 1101011₂ - 111010₂
1101011
+111010
_______
0110001
_______
1101011₂ - 111010₂ = 110001₂

a) The method of repeated multiplication by 2 has to be used to convert such kind of decimal fractions.
The steps involved in the method of repeated multiplication by 2:
Step 1: Multiply the decimal fraction by 2 and note the integer part. The integer part is either 0 or 1.
Step 2: Discard the integer part of the previous product. Multiply the fractional part of the previous product by 2. Repeat Step 1 until the same fraction repeats or terminates (0).
Step 3: The resulting integer part forms a sequence of 0s and 1s that become the binary equivalent of decimal fraction.
Step 4: The final answer is to be written from first integer part obtained till the last integer part obtained.
b) (98.46)₁₀
1. Integer part

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

S.No	Generation	Period	Main Component used	Merits/ Demerits
1	First Generation	1940 - 1956	Vaccum tubes	1. Big in size 2. Consumed more power 3. Malfunction due to over heat 4. Machine Language was used
First Generation Computer - ENIAC, EDVAC, UNIVAC 1 ENIAC weighed about 27 tons, size 8 feet x 100 feet x 3 feet and consumed around 150 watts of power
2	Second Generation	1956-1964	Transistors	1. Smaller compared to First Generation 2. Generated Less Heat 3. Consumed less power compared to first generation 4. Punched cards were used 5. First operating system was developed - Batch Processing and Multiprogramming Operating System 6. Machine language as well as Assembly language was used.
Second Generation Computers - IBM 1401, IBM 1620, UNIVAC 1108
3	Third Generation	1964-1971	Integrated Circuits (IC)	1. Computers were smaller, faster and more reliable 2. Consumed less power. 3. High-Level Languages were used
Third Generation Computers -IBM ·360 series, Honeywell 6000 series
4	Fourth Generation	1971-1980	Microprocessor Very Large Scale Integrated Circuits (VLSI)	1. Smaller and Faster 2. Microcomputer series such as IBM and APPLE were developed 3. portable Computers were introduced
5	Fifth Generation	1980-till date	Ultra Large Scale Integration (ULSI)	1. Parallel, Processing 2. Super conductors 3. Computers size was drastically reduced. 4. Can recognize Images and Graphics 5. Introduction of Artificial Intelligence and Expert Systems 6. Able to solve high complex problems including decision making and logical reasoning
6	Sixth Generation	In future		1. Parallel and Distributed computing 2. Computers have become smarter faster and smaller 3. Development of robotics 4. Natural Language Processing 5. Development of Voice Recognition Software.

(i) Professional Graphic Design: Even the user don't have graphic design experience, they know how to make adjustments to existing graphics.
(ii) Branding: Templates can easily be modified by changing colors, fonts, graphics etc.
(iii) Speed: With a good starting point in each slide, the presentation is made in a snap.
(iv) Quick customization: It's much easier to edit the template in its original form, not as a copy of a copy.
(v) Consistency: A consistent design scheme will avoid Jarring transitions and sneaking suspicion that the presentation was pasted together as a ransom note.

1. = Sum (B5 : E5) = 4285
2. = Sum (E2 : E6) = 1600
3. = Sum (C5 : D6) = 4395
4. = Average (B2 : B6) = 1760
5. = Average (B2 : B6) = 1760
5. =(B6 - E6) = 1700

(i) Page formatting: The most important thing in a word processor is how to format the page with elements such as margins, numbering, page layout, headers and footers. Formatting your pages makes it look more attractive and make it easier to read.
(ii) Changing page size : The default page size in writer is 8.5 \(\times\) 11^'', the same as that of a standard A4 printing paper. However, for different types of documents, you may need to change the page size.To change the paper size:
Select the page to be resized.
Select Format \(\rightarrow\) Page, the page style dialog box
Select Page Tab
In the paper format group, select the format like A4, legal etc.
Or the width and height option can be used to set the page size.
(iii) Changing page margins :Changing or setting page margins in OpenOffice Writer can be done in two ways :
Using the Rulers - quick and easy, but does not have precise values.
Using the Page Style dialog box - can specify precise values for the margins.
1. Changing page margins - using Ruler.
The shaded sections of the rulers are the margins.
Hold the mouse pointer over the line between the gray and white sections.
The mouse pointer turns into a double-headed arrow.
Hold down the left mouse button and drag the mouse to move the margin and release it at the required point.
The new margin is set.
2. Using the Page Style dialog box.
To change margins using the Page Style dialog box
1. Right-click anywhere on the page and select Page from the popup menu and select page tab of Page Style dialog box as shown.
2. In the Margins group, specify the values for left,right, top and bottom margins.
3. Click ok button.
Orientation : Page orientation refers to how the document will be displayed On screen and printed. There are two different orientations:
Landscape - The width of the document is more than the height. This is best suited for displaying professional photos, invitations, albums, tables etc.

Portrait - This is the most common and default orientation.Here, the height of the document is more than the width. Normally books, newspapers will be displayed in this format.

To change the orientation :
Select the page whose orientation is to be changed
In the Page Style dialog box, under the Orientation group,
Select Portrait or Landscape button.
Click ok button.
Page colour and borders: Changing the page color is not quite common. To do so, in the Page Style dialog box,select Background tab, In As option click on color and select the color" from the color palette or select "graphic" to apply an image as a page background.