💻 Basics of Computer Fundamental & Application (TCA-100T)

UNIT 1 — Introduction & Evolution of Computers

1.1 Computer kya hai?

Aasan bhasa me: Input → Process → Output + Storage — yahi computer ka chakra hai.

        +-------------------+
Input ->|   PROCESSING      |-> Output
        |   (CPU + Memory)  |
        +-------------------+
                 |
              STORAGE
   (Input devices: keyboard, mouse, scanner, mic)
   (Output devices: monitor, printer, speaker)
   (Processing: CPU - ALU + CU + Registers)
   (Storage: HDD, SSD, Pen drive, Cloud, RAM)

1.2 Data vs Information

1.3 Characteristics of Computer (Features — 8 points)

Limitations of Computer (kaunse kaam nahi kar sakta)

• No self-thinking: Instructions ke bina kuch nahi kar sakta — "zero IQ" machine.
• No decision (without program): Khud se judgement nahi leta.
• No feelings/emotions: Empathy, care, moral judgement nahi.
• Dependency: Bijli, hardware aur software aur human operator chahiye.
• Hardware failure ka risk: System crash, virus, data loss.
• Unemployment ka concern: Automation se kuch jobs par asar.
• Cost & maintenance: Setup aur regular maintenance mehnga.

1.4 Evolution / History of Computers (Generations — super important)

Important "First" facts (objective/viva ke liye)

1.5 Types of Computers

(A) Working principle ke hisaab se

(B) Size, speed aur capacity ke hisaab se

1.6 Computer Architecture (Block Diagram) & Organisation

                       COMPUTER SYSTEM
+---------------------------------------------------------------+
|                    CENTRAL PROCESSING UNIT (CPU)              |
|  +----------------+   +----------------+   +----------------+  |
|  |   ALU          |<->|   CONTROL      |<->|   REGISTERS    |  |
|  | (Arithmetic &  |   |   UNIT (CU)    |   | (temporary     |  |
|  |  Logic: +,-,*,/|   | fetch-decode-  |   |  fast storage) |  |
|  |  compare)      |   | execute control|   |                |  |
|  +----------------+   +----------------+   +----------------+  |
+-----------------------------|---|-----------------------------+
                              |   |
        PRIMARY MEMORY        |   |        SECONDARY STORAGE
        (Main Memory)         |   |   (HDD, SSD, Pen drive, DVD)
        RAM + ROM             |   |
              |               |   |
              +-------+-------+---+
                      |
              SYSTEM BUS (Data bus, Address bus, Control bus)
                      |
        +-------------+--------------+
        |                            |
   INPUT DEVICES                OUTPUT DEVICES
   Keyboard, Mouse,             Monitor, Printer,
   Scanner, MIC, Webcam         Speaker, Plotter, Projector

Main units ka kaam

1.7 Registers (CPU ke andar ki tiny memory)

Instruction Cycle (CPU kaise kaam karta hai — 4 steps)

1. FETCH    - PC ke address se instruction memory se laao
2. DECODE   - CU samjhe ki instruction kya keh rahi hai
3. EXECUTE  - ALU/CU kaam kare (add, compare, move data)
4. STORE    - Result ko register/memory me rakho, PC ko next par badhao
   (ye cycle billions of times per second chalta hai - 3 GHz CPU = 3 billion cycles/sec)

1.8 Storage ke Units (bits se TB tak)

1 Bit        = 0 ya 1 (sabse chhoti unit)
1 Nibble     = 4 bits
1 Byte       = 8 bits (ek character, jaise 'A' ya '5')
1 KB (Kilobyte) = 1024 Bytes
1 MB (Megabyte) = 1024 KB
1 GB (Gigabyte) = 1024 MB
1 TB (Terabyte) = 1024 GB
1 PB (Petabyte) = 1024 TB
1 EB (Exabyte)  = 1024 PB
1 ZB (Zettabyte)= 1024 EB
1 YB (Yottabyte)= 1024 ZB
Note: 1024 (2^10) hota hai, 1000 nahi - kyunki computer binary (0/1) me chalta hai.

UNIT 2 — CPU, Input-Output Devices, Memory, Number System & Boolean Algebra

2.1 Input Devices

2.2 Output Devices

2.3 Memory (Computer ki yaad)

Memory Hierarchy (upar = fast + costly + kam size)

Registers            -> CPU ke andar, fastest, smallest
   |  Cache (L1, L2, L3) -> CPU ke paas, super fast, mehenga
   |     |  RAM (Main memory) -> programs run ke liye
   |     |     |  Secondary storage (HDD/SSD/Pen drive) -> permanent
   |     |     |     |  Cloud storage -> bahar ke server par

RAM vs ROM

Cache Memory & Virtual Memory (bonus concepts)

• Cache Memory: CPU aur RAM ke beech ki super-fast chhoti memory — frequently used data ki copy rakhti hai. L1 (fastest, chhoti), L2, L3 (badi, thodi slow). Isse speed badhti hai.
• Virtual Memory: Jab RAM full ho jaaye, to computer HDD/SSD ke ek hissa ko "RAM jaisa" use karta hai (page file/swap). Slow hota hai par crash nahi hone deta.
• Buffer: Temporary holding area — jaise printer spool, YouTube video ka buffering.
• BIOS: Basic Input Output System — ROM me likha program jo komputer start karte waqt POST (power-on self-test) karke OS load karta hai.

Secondary Storage Devices

2.4 CPU & Memory kaise kaam karte hain (step-by-step)

Jab tum "Excel" par click karte ho:
1. HDD/SSD se Excel ka program code RAM me load hota hai
2. CPU ka CU instruction fetch karta hai (Memory se RAM se)
3. Decode -> Execute: ALU calculations karta hai, values register me aati hain
4. Result RAM me jata hai, screen par display (output) hoti hai
5. Tum file save karte ho -> RAM se HDD/SSD me data likha jaata hai
Speed note: Register > Cache > RAM > SSD > HDD > Cloud (network)
Isliye RAM 8 GB se 16 GB karne par laptop "fast" feel hota hai - kam swapping.

2.5 Number System & Conversions

(A) Decimal to Binary — Division method

Example 1: (25)10 = ?
25 / 2 = 12 remainder 1  (LSB - last likhna)
12 / 2 =  6 remainder 0
 6 / 2 =  3 remainder 0
 3 / 2 =  1 remainder 1
 1 / 2 =  0 remainder 1  (MSB - sabse pehle likhna)
Jawab (neeche se upar padho): 11001
=> (25)10 = (11001)2

Example 2: (45)10 = ?
45/2=22 r1, 22/2=11 r0, 11/2=5 r1, 5/2=2 r1, 2/2=1 r0, 1/2=0 r1
=> neeche se upar: 101101
Jawab: (45)10 = (101101)2

(B) Binary to Decimal — Power method

Har bit ko 2 ki power se multiply karo (right se left: 2^0, 2^1, 2^2...)
Example 1: (11001)2
= 1x2^4 + 1x2^3 + 0x2^2 + 0x2^1 + 1x2^0
= 16 + 8 + 0 + 0 + 1 = 25
=> (11001)2 = (25)10  ✅ (upper wale ka ulta - sahi hai!)

Example 2: (101101)2
= 1x32 + 0x16 + 1x8 + 1x4 + 0x2 + 1x1
= 32+8+4+1 = 45
=> (101101)2 = (45)10  ✅

(C) Decimal ↔ Hexadecimal / Octal, aur Binary-Octal-Hex shortcut

Decimal to Hex (16 se divide):
(255)10: 255/16 = 15 r 15 (F)   => 15/16 = 0 r 15 (F)
Jawab: (255)10 = (FF)16  (koi bhi colour code dekho: #FF0000 me FF hai)

Binary to Hexadecimal (4-4 bits ka group banao):
(1101 1010)2 -> 1101 = D (13), 1010 = A (10) -> (DA)16

Binary to Octal (3-3 bits ka group banao):
(101 110)2 -> 101 = 5, 110 = 6 -> (56)8

Hex to Decimal:
(2A)16 = 2x16 + 10 = 42  => (2A)16 = (42)10

2.6 Boolean Algebra & Logic Gates

Three basic logic gates

Truth Tables (inhe ratta maar do — pakka aata hai)

AND Gate                    OR Gate                   NOT Gate
A  B  | Y = A.B              A  B  | Y = A+B             A  | Y = A'
0  0  |   0                  0  0  |   0                 0  |   1
0  1  |   0                  0  1  |   1                 1  |   0
1  0  |   0                  1  0  |   1
1  1  |   1                  1  1  |   1

NAND (AND ka ulta)           NOR (OR ka ulta)         XOR
A  B  |  Y                   A  B  |  Y                 A  B  |  Y (alag hone par 1)
0  0  |  1                   0  0  |  1                 0  0  |  0
0  1  |  1                   0  1  |  0                 0  1  |  1
1  0  |  1                   1  0  |  0                 1  0  |  1
1  1  |  0                   1  1  |  0                 1  1  |  0
Note: NAND aur NOR "universal gates" hain - inhi se saare gate bana sakte hain.

Basic Boolean Laws (identity yaad rakho)

UNIT 3 — Software, Operating System & Languages

3.1 Software kya hai? Aur uske types

                     SOFTWARE
                        |
        +---------------+---------------+
        |                               |
   SYSTEM SOFTWARE              APPLICATION SOFTWARE
   (computer ko chalane ke liye)  (user ke kaam ke liye)
        |                               |
  1. Operating System (Windows,      1. General purpose (MS Word,
     Linux, macOS, Android, iOS)       Excel, Chrome, Tally)
  2. Language translators            2. Customised / Tailor-made
     (Assembler, Compiler,             (school ERP, hospital software)
     Interpreter)                    3. Utility (Antivirus, WinZip,
  3. Utility programs                 backup tool, disk cleaner)
     (antivirus, backup, disk tool)  4. Presentation/Graphics
  4. Device drivers                   (PowerPoint, Photoshop)
  5. Firmware (BIOS)

3.2 Operating System (OS)

Functions of OS (ye 8 point pakka likho)

Classification of OS

System Programs (ye OS ke saath aate hain)

• Loader: Program ko disk se memory me load karta hai.
• Linker: Alag-alag compiled modules ko jodkar ek program banata hai.
• Utility programs: Backup, disk defragmenter, antivirus, compression (WinZip/WinRAR), file manager.
• Device drivers: Printer/scanner/graphics card ko OS se baat karwana.
• Compiler/Assembler/Interpreter: Language translator (neeche detail me).
• Bootstrap/BIOS: Start-up ke waqt system check (POST) aur OS load.

3.3 Popular Operating Systems (DOS, UNIX, LINUX, Windows)

DOS ke important commands (practical/viva ke liye)

3.4 Language Translators & Programming Languages

Levels of Languages

Translators (3 types — very important table)

UNIT 4 — Computer Networks & Internet

4.1 Computer Network kya hai?

Objectives / Advantages of Networking

• Resource sharing: Ek printer, ek internet connection, ek server — sab use kar sakte hain (cost bachti hai).
• Communication: Email, chat, video call — instant messaging.
• File & data sharing: Ek jagah file rakh do, sab access kar lein.
• Cost saving & efficiency: Software ki ek hi copy centrally manage ho jaati hai.
• Backup & reliability: Data duplicate karke safety milti hai.
• Centralised administration: IT staff ek jagah se sab manage karta hai.

Disadvantages

• Setup cost (cables, switches, server, IT staff).
• Security risk — hacking, virus, data leak.
• System dependency — server down to poori company ka kaam rukta hai.
• Management complex — IP, permissions, troubleshooting.

4.2 LAN, MAN aur WAN

4.3 Data Communication & Transmission

4.4 Network Topologies (layout/structure)

4.5 Internet Basics

4.6 Web Browsers, Search Engines & Social Networking

4.7 Email — kaise likhein (format bhi aata hai)

Email ke parts:
  From:      tumhara email address
  To:        receiver ka email (ek ya zyada)
  CC:        Carbon Copy (sabko dikhta hai ki kis-kis ko bheja)
  BCC:       Blind CC (baaki logon ko ye naam nahi dikhta - privacy)
  Subject:   short title (jaise "Application for fee concession")
  Body:      Greeting -> message -> closing
  Attachment: file (PDF/photo) - 25 MB tak mostly

Sample email (leave application to Principal):
  To: principal@college.edu
  Subject: Application for 3 days leave (14-16 Oct)

  Respected Sir/Madam,
  I am Anshu, BBA Semester 1 student of Roll No. 21. I have fever
  and the doctor has advised rest for three days. Kindly grant me
  leave from 14 to 16 October 2026.
  I will complete my pending work after returning.
  Thank you.
  Sincerely,
  Anshu / BBA Sem 1 / Roll 21 / 9876543210

Email ke fayde: 2 second me duniya me kahi bhi pahunch jata hai, free,
record rehta hai, ek saath 100 logon ko, file + photo bhej sakte ho.
Email ke nuksan: spam, phishing fraud, internet zaroori, formal tone
ka dhyan rakhna padta hai.

UNIT 5 — Word Processing, MS Excel & PowerPoint

5.1 Word Processing (MS Word / LibreOffice Writer)

Basic operations (steps ke saath)

5.2 MS Excel (Spreadsheet)

Basic Structure

Workbook (poori file .xlsx)
   |-- Sheet 1 (worksheet)
   |-- Sheet 2
   |-- Sheet 3 ...
Each sheet = Columns (A, B, C... IV, XFD tak) + Rows (1, 2, 3... 10,48,576 tak)
Cell = ek box (Column + Row milakar: A1, B5, C10)
Cell Range = A1:D10 (block)
Active cell = jis cell par currently cursor hai
Formula Bar = formula dikhne/edit karne wali jagah
Name Box = aktive cell ka address

Important Excel Terms

Common Formulas & Functions (ratta maar lo — practical me aayega)

Basic math:     =A1+B1   =A1-B1   =A1*B1   =A1/B1   =A1^2 (power)
AutoSum:        =SUM(A1:A10)
Average:        =AVERAGE(B2:B31)
Count:          =COUNT(A1:A10)         (sirf numbers)
                =COUNTA(A1:A10)        (non-empty cells)
Max / Min:      =MAX(B2:B31)  =MIN(B2:B31)
Round:          =ROUND(A1,2)
Percentage:     =B2/Total*100   or  =B2/$B$10*100 (absolute ref)
IF (condition): =IF(B2>=33,"Pass","Fail")
IF + AND/OR:    =IF(AND(B2>=33,C2>=33),"Pass","Fail")
Nested IF:      =IF(B2>=75,"A",IF(B2>=60,"B",IF(B2>=45,"C","D")))
Lookup (VLOOKUP): =VLOOKUP(A2, $D$2:$F$50, 3, FALSE)
                   (A2 ko dhoondo table D2:F50 me, 3rd column se value laao)
SUMIF:          =SUMIF(C2:C100,"Chai",D2:D100)  (category Chai ka total)
COUNTIF:        =COUNTIF(B2:B100,"Fail")
Concatenate:    =A2&" "&B2  or  =CONCAT(A2,B2)
Trim / Len:     =TRIM(A2)  =LEN(A2)
Date:           =TODAY()  =NOW()  =YEAR(A2)
Text join:      =TEXTJOIN(", ",TRUE,A2:A5)

5.3 MS PowerPoint (Presentation)

Basic Steps (create → save → print)

Step 1  New presentation kholo (Blank ya Template/Design chois)
Step 2  Slide add karo (Home > New Slide ya Ctrl+M)
        - Slide layouts: Title Slide, Title+Content, Two Content, Picture with Caption
Step 3  Content daalo:
        - Text: title box + content box (font, size, color)
        - Insert > Picture / Chart / Table / SmartArt / Video / Shape
Step 4  Format karo:
        - Themes/Design (colours, fonts), Slide size (4:3 ya 16:9)
        - Slide Master se poora design ek jagah set karo
        - Notes me speaker points likho
Step 5  Animation & Transition (halka rakho):
        - Transition: slide ke beech ka effect
        - Animation: ek slide ke andar text/image ka effect
        - Duration + order set karo, "On Click" ya "After 2 sec"
Step 6  Slideshow chalao:
        - F5 = start from beginning, Shift+F5 = current slide se
        - Slide Show > From Beginning, Presenter view
        - B = black screen, . (dot) = white screen, Esc = exit
Step 7  Save & export:
        - Save as .pptx (Ctrl+S)
        - File > Export > PDF (print/notes ke liye)
        - Print: Page setup (handouts - 2,4,6 slides per page / outline)

MS Office shortcuts — ek jagah (common for all)