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MULTIPLEXERS -  Multiplexer ek digital switch hota hai, jise MUX kaha jata hai.MUX ka kaam hota hai bahut saare input signals ko output se connect karna.Isme bahut saare inputs ko combine karke only one output ko generate kiya jata hai.It is many to one process.It has data select inputs which determine which data source is connected to the output.The 4 to 1 multiplexer-

The Truth Table of the above multiplexer is as follows-S1S0Y 00 D0 0 1 D1 1 0 D2 1 1 D3 
The logical diagram of 4 to 1 multiplexer is as follows-

There can be different types of multiplexers as-2 to 14 to 18 to 116 to 132 to 1, and many more.Multiplexers ke data select inputs ko find out karne ke liye, Agar 2n input lines hain, then n data select lines hongi, means,2 to 1 multiplexer mein 1 data select input hoga. 21 = 2.4 to 1 multiplexer mein 2 data select input honge. 22 = 4.8 to 1 multiplexer mein 3 data select input honge. 23 = 8.16 to 1 multiplexer mein 4 data select input honge, and 24 = 1632 to 1 multiplexer mein 5…

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So, aaj hum combinational circuits mein encoders and decoders topic ke baare mein understand karenge.
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ENCODERS -  Encoder ek device hai jisse hum use karte hain signals ko codes mein convert karne ke liye.Then, uss code ko various purposes ke liye use kiya jata hai such as, compress the data to transmit, encryption, translate this code to another code, and many more.Encoder mein 2n input values hoti hain and n output values.Agar output code mein input code se less values hain, so usse encoder kaha jata hai.Encoder mein jyada input values ko encode karke less output values ko generate kiya jata hai.The binary-to-octal encoder is there in which hum binary se octal mein convert karenge, so the input values are 8, and output values are 3.Ek time par only ek input line ki value 1 ho sakti hai.Truth table of binary-to-octal is as follows-
d0d1d2d3 d4 d5 d6 d7 a2 a1 a0100 0 0 0 0 0 0 0 0 01 0  00 0 0 0 0 0 1 0 0 1 0 0 0 0 …

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Today we are going to discuss about the Combinational Circuit, Adders and Subtractors specifically.
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COMBINATIONAL CIRCUITS - Combinational circuits wo digital circuits hote hai jisme current input se hum output lete hain. Isme memory elements ko consider nahi kiya jata hai. Combinational Circuit mein kya output ayegi wo completely depend karti hai uski input values par. Basically the combinational circuits are as follows- AddersSubtractorsEncoderDecoderMultiplexerDemultiplexer
Combinational circuits ko design karne ke liye there are following steps- Problem ko clearly understand karna,Then, input and output variables ko find out karna, konsi input value hai and konsi output value hai.Then, input and output variables ko letters or symbols ki form mein assign karna.I/O symbols ko represent karne ke liye Truth Table create karna.Then, is truth table se boolean functions ko find karna.Ab boolean expressions ko solve karna…

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Today we will going to study about the logical circuits basic introduction.
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LOGICAL CIRCUITS - Basically logical gates connected hote hain, ek gate ki output doosre gate ki input hoti hai, then isko logical circuit kehte hain.  In digital systems, logical circuits are of 2 types- Combinational CircuitsSequential Circuits1. COMBINATIONAL CIRCUITS -  In Combinational Circuits, the output is determined by the current input state only.Means, the output depends on inputs only, at a given point of time.Isme memory element ko consider nahi kiya jata.Combinational circuits ko design karne ke liye only Gates and Circulatory lines ko use kiya jata hai. It is easy to design.The speed is fast.It is less expensive.Combinational Circuits examples are-AddersSubtractorsDecodersEncodersMultiplexersDemultiplexers
2. SEQUENTIAL CIRCUITS -  In Sequential Circuits, the output is determined by current input state along with memory elements.T…

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So, aaj hum computer system architecture mein logical gates ke baare mein study karenge,
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Boolean algebra has 3 operations basically, which are AND, OR, and NOT, it corresponds to the electronic circuit as AND, OR, and NOT Gates.  AND is represented as . OR is represented as + NOT is represented as '
AND, OR, and NOT Gates ki help se hum Boolean functions ke logical diagram ko design kar sakte hain. 
Note that- NAND and NOR Gates are called Universal Gates, because other gates can be derived from NAND and NOR Gates, Other gates can be - AND, OR, NOT, XOR, XNOR. 
Logical gates mein hum various inputs de sakte hain and it produces one output as function.
For an example,  Design a logical diagram for the function
F=X'Y+XY'+Z'.
So, the logical diagram of the above function F is as follows- Here, X' means complement of X, and so on. Here, ' means complement.
X'Y, XY' represented as X' and Y, and …

Hello Dear Students,
Hope you all are doing good...
So, aaj hum boolean algebra topic ko cover karenge,
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BOOLEAN ALGEBRA - Boolean Algebra was first developed by George Boole in 1854, but the formal definition was given by E.V.Huntington in 1904.Boolean ka matlab hota hai true or false, here 0 and 1.Boolean Algebra is a branch of mathematics algebra.Boolean algebra is set of 3 operations which are-+ (similar to logical OR), also denoted as ∨ ・(similar to logical AND), also denoted as ∧ー (NOT), also denoted as prefix ᄀThere are only 2 values i.e. 0 and 1, agar hum koi bhi operation perform karenge so uska result 0 and 1 mein hi ayega, whether 0, 1, or combination of 0 and 1. The Truth Table of these 3 operations, AND, OR, NOT as as follows- 
Truth Table for ANDA B R 0 0 0 0 1 0 1 0 0 1 1 1 
Truth Table for ORA B R 0 0 0 0 1 1 1 0 1 1 1 1 

Truth Table for NOTA R 0 1 1 0 
PRECEDENCE OF BOOLEAN OPERATIONSOperator Symbol Precedence         Parenthesis ( ) First Priority …

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Aaj hum computer arithmetic ke baare mein study karenge, means computer mein kaise arithmetic perform hote hain, addition, subtraction, multiplication, division.
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As we all know, computer can only understand the binary language, means 0s and 1s. So, computer mein jab bhi operations perform kiye jate hain, wo binary form mein kiye jate hain.  Basically, the computer arithmetic deals with the method of representing fixed and floating-point numbers in digital systems.
Computer arithmetic performs on binary numbers- Binary AdditionBinary SubtractionBinary MultiplicationBinary Division
1. BINARY ADDITION - Binary addition mein hum 0s and 1s hi lete hain, isme hum binary numbers mein addition operation perform karte hain. Binary addition perform karne ke liye 2 situations hoti hain, which are- Half Adder - Half Adder mein 2 input values hoti hain and 2 output values hoti hain.Full Adder - Full Adder mein 3 input values hoti ha…

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So, in previous lecture, we have studied about the number system, and now we will study about the conversions of number system.
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Ek number system ko doosre number system mein convert karne ke liye various conversions technique use ki jati hai. The possible types of conversions are as follows- Other Base System to DecimalDecimal to Other Base SystemOther Base System to Non-Decimal
1. OTHER BASE SYSTEM TO DECIMAL - Binary number, octal number and hexadecimal number ko Decimal number mein convert karne ke liye following steps- Find place value of each digit, place value is the base of number system.Multiply the place value with their place holders.Find the sum of all products. Number in any base Conversion Decimal Number  Binary Number (1010)        1*23+0*22+1*21+0*20   
=1*6+0*4+1*2+0*1
=6+0+2+0
=8  8 Octal Number(504)5*82+0*81+4*80
=5*64+0*8+4*1
=320+0+4
=324  324Hexadecimal Number(A6)  A*161+6*160
=10*16+6*1
=160+16
=166  166
W…

Hello Dear Students,Hope you all are doing good..
Aaj hum computer number system ke baare mein study karenge,
So, let's get started.... Computer system ki language Binary language hoti hai.Binary Language means 0s and 1s.User jo bhi input deta hai, computer usse binary form mein convert karke processing karta hai, because computer system can understand only 0s and 1s. So, hum discuss karenge binary numbers ko.Decimal Number             Binary Number Explanation   0    0 Since we take only 0 and 1, so first comes 0 1 1 Now, the next of 0 is 1, so here value of decimal no 1 is 1 2 10After 1, there is 10 in which 0 and 1 comes,
because from 2 to 9, there is no 0 and 1.  3 11After 10, 11 has 0 or 1.which is 11.  4 100After 11, there is only 100 which is 0 and 1s. 5 101 Next is 101,thus 5 is stored in computer as 101. 6 110 Next is 110,thus 6 is stored in computer as 110. 7 111 Next is 111, thus 7 stores in computer as 111. 8 1000 After 111, there comes 1000, where 0 and 1 comes. 9 1001 N…

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So, after input and output peripheral devices, we will study about Memory peripheral devices.
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Peripheral devices wo devices hote hain jo ki system ke saath externally connect kiye jate hain so that computer se information li ja sake and computer ko information di ja sake. 
MEMORY DEVICES -  Memory means storage space jisme sab kuch save kiya jata hai and store karaya jata hai.Jab user input devices se system ko input deta hai, then wo memory mein ja kar store ki jati hai.Then, wo input ko process kiya jata hai so that output can be produced.Their is a difference between memory and storage,Memory refers to the amount of RAM installed in the computer, andStorage refers to the capacity of computer hard disk.The various secondary storage devices are as follows-Magnetic TapeMagnetic DiskFloppy DiskHard DiskCD-ROM
1. MAGNETIC TAPE -  Magnetic Tape basically data ko store karne ke liye use hoti hai.It is basically a tape, and…