Knowledge?
What is knowledge❓
Knowledge is the collection of facts, information, skills, and understanding that a person gains through learning, experience, observation, and education.
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Types of Knowledge
1. Theoretical Knowledge
Understanding concepts, laws, principles, and ideas.
2. Practical Knowledge
Skills learned through real-life experience and practice.
3. Experiential Knowledge
Knowledge gained from personal experiences.
4. Technical Knowledge
Information related to technology, tools, and digital skills.
5. Social Knowledge
Understanding people, society, culture, and communication.
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Sources of Knowledge
Books and Education
Teachers and Mentors
Real-life Experiences
Internet & Digital Media
Observation and Research
Practice and Experiments
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Importance of Knowledge
Helps in making better decisions
Builds confidence and personality
Improves problem-solving skills
Opens the door to career success
Encourages creativity and innovation
Makes you independent and aware
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Characteristics of Knowledge
Infinite – The more you learn, the more there is to explore.
Powerful – Knowledge gives strength and confidence.
Transferable – You can share it with others.
Evolving – It keeps changing and improving with time.
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Why Should We Gain Knowledge?
Because knowledge shapes our thinking, improves our understanding of the world, and helps us grow as better human beings.
All information for coding
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📌 What is Coding?
Coding (programming) is the process of giving instructions to a computer to perform tasks.
Computer understands only binary (0 and 1), so programmers use languages like Python, Java, C, HTML, JavaScript to communicate with computers.
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📌 Why Coding is Important?
Helps build apps, websites, software, games
Improves logical thinking
High-demand career with good salary
Automates tasks
Needed in AI, machine learning, data science, cybersecurity
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📌 Types of Coding / Programming
1. Web Development
Frontend → HTML, CSS, JavaScript
Backend → Python, PHP, Java, Node.js
Full-stack → Front + Back end both
2. App Development
Android → Kotlin, Java
iOS → Swift
Cross-platform → Flutter, React Native
3. Game Development
Unity (C#)
Unreal Engine (C++)
4. Data Science & AI
Python (NumPy, Pandas, TensorFlow)
R Language
Machine Learning
5. Cyber Security
Python
Networking
Kali Linux tools
6. Software Development
Java
C++
C#
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📌 Popular Programming Languages
Language Use
Python Easy, AI/ML, automation
Java Apps, software, backend
C++ Games, system software
C Operating systems, embedded
JavaScript Websites
PHP Websites + backend
SQL Database management
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📌 How Does Coding Work? (Simple Explanation)
1. You write code → example in Python
print("Hello World")
2. Computer reads instructions
3. Executes the task
4. Shows output
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📌 Core Concepts of Coding
✔ Variables
Store data
✔ Data Types
Number, text, boolean
✔ Conditions
if, else
✔ Loops
Repeat tasks
✔ Functions
Reusable blocks of code
✔ Arrays / Lists
Store multiple values
✔ Classes & Objects (OOP)
Used in Java, Python, C++
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📌 Example — Python Code
name = "John"
for i in range(3):
print("Hello", name)
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📌 Coding Career Opportunities
Web developer
App developer
Software engineer
Game developer
AI engineer
Data scientist
Ethical hacker
Cloud engineer
DevOps engineer
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📌 How to Start Coding? (Beginners Roadmap)
Step 1: Choose a language
→ Python (easiest for beginners)
Step 2: Learn basics
Variables
Loops
Conditions
Functions
Step 3: Build small projects
Calculator
To-do app
Website
Step 4: Practice daily
Use platforms like
HackerRank
LeetCode
CodeChef
Step 5: Build portfolio (GitHub)
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📌 Best Resources to Learn Coding
Free Resources
W3Schools
Geeks for geeks
Tutorial point
Codecademy (free parts)
Paid Courses
Udemy
Coursera
🌟 JAVA – Full Information (Complete Guide)
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1. What is Java?
Java is a high-level, object-oriented programming language used to build:
Mobile apps (especially Android apps)
Web applications
Desktop software
Games
Cloud-based applications
Creator: James Gosling
Company: Sun Microsystems (later acquired by Oracle Corporation)
Year: 1995
Main Principle:
➡ WORA (Write Once, Run Anywhere) — code runs on any device that has the Java Virtual Machine (JVM).
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2. Features of Java
✔ 1. Simple and easy
Syntax is simple and similar to C/C++.
✔ 2. Object-Oriented
Uses classes and objects.
✔ 3. Platform Independent
Runs on JVM, not directly on OS.
✔ 4. Secure
Strong memory management, no pointers, automatic garbage collection.
✔ 5. Robust
Handles errors well and avoids crashes.
✔ 6. Multithreaded
Can run multiple tasks at the same time.
✔ 7. High Performance
Uses JIT compiler for fast execution.
✔ 8. Distributed
Supports networking easily.
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3. Java Architecture
Java has 3 main components:
1️⃣ JDK (Java Development Kit)
Used for developing Java programs.
2️⃣ JRE (Java Runtime Environment)
Used for running Java programs.
3️⃣ JVM (Java Virtual Machine)
Converts bytecode to machine code.
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4. How Java Works
1. You write code → MyFile.java
2. Compiler converts it to → MyFile.class (bytecode)
3. JVM runs bytecode on any OS
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5. Java Syntax (Basic Program)
class Hello {
public static void main(String[] args) {
System.out.println("Hello World!");
}
}
Explanation:
class → creates a class
main → starting point of program
System.out.println() → prints text
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6. OOP Concepts in Java
1. Class
Blueprint of an object.
2. Object
Instance of a class.
3. Inheritance
One class inherits another.
4. Polymorphism
Many forms of the same function.
5. Encapsulation
Hiding data using private keywords.
6. Abstraction
Showing important details only.
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7. Important Java Topics List
Here is everything you must learn in Java:
Basics
Variables
Data Types
Operators
Input/Output
Conditional Statements
Loops
Intermediate
Arrays
Strings
Methods
OOP Concepts
Packages
Exception Handling
Advanced
Multithreading
File Handling
Collections Framework
Generics
JDBC
Networking
Lambda Expressions
Streams API
Professional-Level
JavaFX / Swing
Servlets & JSP
Spring Framework (Spring Boot)
Hibernate
Microservices
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8. Where Java Is Used
📱 Android App Development
Java is official language for Android development before Kotlin.
🌐 Web Development
Used in backend using Servlets, JSP, Spring Boot.
🏢 Enterprise Applications
Used by banks, companies, startups.
🌩 Cloud & Big Data
Java is used in tools like
Hadoop
Apache Spark
🎮 Games
Used in Minecraft (Java Edition).
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9. Popular Java Frameworks
1. Spring Boot – Backend apps
2. Hibernate – Database
3. JavaFX – Desktop apps
4. Struts – Web apps
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10. Advantages & Disadvantages
✔ Advantages
Platform independent
Secure
Stable
Large community support
High demand in jobs
❌ Disadvantages
Slower than C++
Uses more memory
Verbose code
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11. Career Options in Java
Job Roles
Java Developer
Android App Developer
Backend Developer
Software Engineer
Full Stack Developer
Companies Using Java
Google
💻 C++ Full Information (Beginner to Advanced)
🔹 1. What is c++?
C++ ek general-purpose, high-performance programming language hai.
✔ Fast, powerful, hardware ke close
✔ Object-Oriented
✔ Games, Operating Systems, Compilers, Real-time systems, Competitive programming sab me use hoti hai.
Invented by: Bjarne Stroustrup
Year: 1985
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🔹 2. C++ Features
⭐ Main Features:
Fast execution
Object-Oriented Programming (OOP)
Memory management (pointers)
Low-level + High-level capabilities
Reusability through classes
Rich libraries (STL)
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🔹 3. C++ Basic Structure
#include <iostream>
using namespace std;
int main() {
cout << "Hello World";
return 0;
}
Explanation:
#include <iostream> → Input/Output library
int main() → Program starts here
cout → Output
return 0; → Program ends successfully
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🔹 4. Variables & Data Types
Basic Types:
int → numbers
float → decimal
double → bigger decimal
char → character
string → words
bool → true/false
Example:
int age = 20;
float price = 55.5;
char grade = 'A';
string name = "Rahul";
bool isPass = true;
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🔹 5. Input/Output
int a;
cin >> a; // input
cout << a; // output
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🔹 6. Operators
Arithmetic → + - * / %
Comparison → == != > < >= <=
Logical → && || !
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🔹 7. Control Statements
✔ if-else
if(age >= 18){
cout << "Adult";
}
else{
cout << "Minor";
}
✔ Loops
For Loop
for(int i=1; i<=5; i++){
cout << i;
}
While Loop
while(x < 10){
x++;
}
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🔹 8. Functions
int add(int a, int b){
return a + b;
}
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🔹 9. Arrays
int arr[5] = {1,2,3,4,5};
cout << arr[2]; // Output: 3
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🔹 10. Object-Oriented Programming (OOP)
✔ Class & Object
class Person {
public:
string name;
int age;
};
int main(){
Person p;
p.name = "Aman";
p.age = 18;
}
✔ OOP Concepts:
Encapsulation
Inheritance
Polymorphism
Abstraction
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🔹 11. Pointers
int x = 10;
int *p = &x;
cout << *p; // Output: 10
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🔹 12. STL (Standard Template Library)
STL Parts:
Containers
vector
set
map
queue
stack
Algorithms
sort()
max()
min()
Iterators
Example:
vector<int> v = {1,2,3};
sort(v.begin(), v.end());
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🔹 13. File Handling
#include <fstream>
ofstream file("data.txt");
file << "Hello";
file.close();
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🔹 14. Advanced Concepts
Dynamic Memory (new, delete)
Templates
Lambda functions
Exception handling
Multithreading
Smart pointers
Namespaces
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🔹 15. C++ Where Used?
✔ Game Development (Unreal Engine)
✔ Operating Systems
✔ Embedded Systems
✔ Banking & Finance
✔ Competitive Programming
✔ Robotics
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🔹 16. Best IDEs for C++
VS Code
Code::Blocks
Dev C++
Turbo C++ (old)
Visual Studio
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🔹 17. C++ Interview/Exam Important Questions
1. What is OOP?
2. What is constructor?
3. What is destructor?
4. Difference: struct vs class
5. What is polymorphism?
6. What is pointer?
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🔹 18. Practice Programs
1. Print numbers 1–100
2. Factorial
3. Prime number
4. Reverse a string
5. Fibonacci series
