(i) MAR (Memory Address Register)
(ii) MDR (Memory Data Register)

Basic set of machine level instructions that a microprocessor is designed to execute is called as an instruction set.

(i) MHz (Mega Hertz)
(ii) GHz (Giga Hertz)

Ultra-violet-rays is used to erase the content of a EPROM.

The most basic unit of information in a digital computer is called a bit. A bit is a binary digit which can be 0, or 1

Bits, Nibble, Bytes, and Word

Step 1: Convert given Decimal number into Binary.
Step 2: Check if the binary number contains 8 bits. if less add 0 at the left most bit, to make it as 8 bits.
Step 3: Invert all bits (i.e. Change 1 as 0 and 0 as 1).

The term data comes from the word datum, which means a raw fact. The data is a fact about people. places or some objects

(i) Microcomputer
(ii) Portal Computers

ENIAC, EDVAC, UNIVAC 1

The primary memory is used to temporarily store the programs and data when the instructions are ready to execute. The secondary memory is used to store the data permanently.

 1)  0 x 0 = 0
 2)  1 x 1 = 1
 3)  1 x 0 = 0
 4)  0 x 0 = 0

1) 0 - 0  = 0
2) 1 - 0 = 1
3) 1 -1  =  0
4) 0 -1  = 1

(i) Computers use binary number system for counting and arithmetic operations.
(ii) The number system has base 2 and it uses 2 digits 0 and 1.
(iii) A string which have any combination of these two digits is called binary number. It would be written as (1001)₂

(365)₈ = 3 x 8² x 6 x 8¹ + 5 x 8^{0
            =} 192 + 48 + 5 = (245)₁₀
(366)₈ = 3 x 8² + 6 x 8¹ + 6 x 8⁰
          = 192 + 42 + 6 = (246)₁₀
(367)₈ = 3 x 8² + 6 x 8¹ + 7 x 8⁰
         = 192 + 42 + 6 = (247)₁₀
In decimal form, the given sequence will be 245, 246, 247, 248, 249, 250. To complete the sequence of Octal number, we need to find the octal equal of 248, 249 and 250

a) AND gate truth table

b) OR Gate Truth table

c) Not Gate Truth Table

8 bit Format of 20₁₀  = 00010100
8 bit format of 25₁₀    = 00011001
20₁₀ + 25₁₀              =    _________
                                   00101101
                                    __________
20₁₀ + 25₁₀ = 00101101₂

(i) IC is short for Integrated Circuit or Integrated Chip.
(ii) The IC is a package containing many circuits, pathways, transistors, and other electronic components all working together to perform a particular function or a series of functions.

(i) Machine language is a collection of binary digits or bits that the computer reads and interprets.
(ii) In first generation, machined language was used.

Impact printers:
(i) These printers print with striking of hammers or pins on ribbon. These printers can print on multipart (using carbon papers) by using mechanical pressure.
For example, Dot Matrix printers and Line matrix printers are impact printers.
(ii) A Dot matrix printer that prints using a fixed number of pins or wires.
(iii) Line matrix printers use a fixed print head for printing.

Input device is used to feed any form of data to the computer, which can be stored in the memory unit for further processing.
Example: Keyboard, mouse, Scanner, Fingerprint scanner, Track Ball, Retinal Scanner, Light pen etc.

(i) The main memory is otherwise called as Random Access Memory. This is available in computers in the form of Integrated Circuits (lCs). It is the place in a computer where the Operating System, Application Programs and the data in current use are kept temporarily so that they can be accessed by the computer's processor.
(ii) The smallest unit of information that can be stored in the memory is called as a bit. The memory can be accessed by a collection of 8 bits which is called as a byte.
(iii) The bytes are referred by 'B'. If a computer has 1 megabyte of memory, then it can store 10,48,576 bytes. (or characters) of information. [Hence 1MB is 1024KB and 1 KB is 1024 Bytes, So 1024X1024 =10,48,576 Bytes].
(iv) RAM is a volatile memory, which means that the information stored init is not permanent. As soon as the power is turned off, whatever data that resides in RAM is lost. It allows both read and write operations.
(v) There are two basic types of RAM Dynamic RAM (DRAM), Static RAM (SRAM).
(vi) These two types differ in the technology they use to hold data. Dynamic RAM being a common type needs to be refreshed frequently. Static RAM needs to be refreshed less often, which makes it faster.
(vii) Hence, Static RAM is more expensive than Dynamic RAM.

Steps for Decimal to Binary Conversion.
Step 1: Divide the decimal number which is to be converted by two which is the base of the binary number.
Step 2: The remainder which is obtained from step 1 is the least significant bit of the new binary number.
Step 3: Divide. the quotient which is obtained from the step 2 and the remainder obtained from this is the second least significant bit of the binary number
Step 4: Repeat the process until the quotient becomes zero.
Step 5: The last remainder obtained from the division is the most significant bit of the binary number. Hence, arrange the number from the most significant bit to the least significant bit (i.e., from bottom to top).

Non-Impact Printers:
(i) These printers do not use striking mechanism for printing. They use electrostatic or laser technology.
(ii) Quality and speed of these printers are better than Impact printers. For example, Laser printers and Inkjet printers are non-impact printers.
Laser Printers:
(i) Laser printers mostly work with similar technology used by photocopiers.
(ii) It makes a laser beam scan back and forth across a drum inside the printer, building up a pattern. It can produce very good quality of graphic images.
(iii) One of the chief characteristics of laser printer is their resolution - how many Dots per inch(DPI). The available resolution range around 1200 dpi. Approximately it can print 100 pages per minute(PPM).

Inkjet Printers:
(i) Inkjet Printers use colour cartridges which combined Magenta, Yellow and Cyan inks to create color tones.
(ii) A black cartridge is also used for monochrome output. Inkjet printers work by spraying ionised ink at a sheet of paper.
(iii) The speed of Inkjet printers generally ranges from 1-20 PPM (Page Per Minute).
(iv) They use the technology offering ink by heating it so that it explodes towards the paper in bubbles or by using piezoelectricity in which tiny electric currents controlled by electronic circuits are used inside the printer to spread ink in jet speed.
(v) An Inkjet printer can spread millions of dots of ink at the paper every single second.

Components of a Computer:
The computer is the combination of hardware and software. Hardware is the physical component of a computer like motherboard, memory devices, monitor, keyboard etc., while software is the set of programs or instructions. Both hardware and software together make the computer system to function. Every task given to a computer follows an Inputprocess - output cycle (IPO cycle).

(i) Input unit: Input unit is used to feed any form of data to the computer, which can be stored in the memory unit for further processing.
Example: keyboard, mouse etc.
(ii) Central Processing Unit: CPU is the major component which interprets and executes software instructions. It also control the operation of all other components such as memory, input and output units.
(iii) Arithmetic and Logic Unit: The ALU is a part of the CPU where various computing functions are performed on data. The ALU performs arithmetic operations such as addition, subtraction, multiplication, division and logical operations.

(iv) Control Unit: The control unit controls the flow of data between the CPU memory and I/o devices. It also controls the entire operation of a computer.
(v) Output Unit: An output unit is any hardware component that convey information to users in an understandable form. Example : Monitor, Printer etc.
(vi) Memory Unit: The Memory Unit is of two types which are primary memory and secondary memory. The primary memory is used to temporarily store the programs and data when the instructions are ready to execute. The secondary memory is used to store the data permanently. The Primary Memory is volatile, that is, the content is lost when the power supply is switched off. The Random Access Memory (RAM) is an example of a main memory. The Secondary memory is non volatile, that is, the content is available even after the power supply is switched off. Hard disk, CD-ROM and DVD ROM are examples of secondary memory.