Programing Concepts

Fundamental Programming Concepts: The Core Toolkit 🛠️

These concepts handle how information is stored and categorized within a program.

Variables 🧩: These are named containers that store values. Their contents can change as the program runs.

Example: Assigning values to variables.
```
age = 25              # Variable 'age' holds an integer
user_name = "Charlie" # Variable 'user_name' holds a string
```
Data Types 🔢: Classifications that tell the computer what kind of data a variable holds (e.g., number, text, or true/false). Type Casting is converting a value from one type to another.

Example: Different basic data types and type casting.
```
# Basic Types
integer_val = 10      # int
float_val = 3.14      # float
is_logged_in = True   # bool

# Type Casting
new_int = int("500")  # Converts string "500" to integer 500
```

Control flow structures dictate the order in which code instructions are executed, enabling decisions and repetition.

Conditionals ⚖️: Statements (if, elif, else) that allow your program to make decisions. A block of code runs only if a specified condition evaluates to True.

Example: The if/else structure.
```
score = 88
if score >= 90:
    print("Excellent!")
elif score >= 80:
    print("Good Job.")
else:
    print("Keep practicing.")
```
Loops 🔁: Structures used to repeatedly execute a block of code. A For Loop repeats for a set number of items, while a While Loop repeats as long as a condition is met.

Example: Repeating an action using loops.
```
# For Loop: Iterating over a range
for i in range(3):
    print(i) # Output: 0, 1, 2

# While Loop: Repeating while a condition is True
x = 0
while x < 2:
    x += 1
```

These concepts allow developers to segment code into manageable, reusable chunks.

Functions ⚙️: Independent, named blocks of code designed to perform one specific task. They often take inputs (arguments) and can return an output.

Example: Defining and calling a function.
```
def calculate_area(length, width):
    return length * width

result = calculate_area(10, 5) # result is 50
```
Methods 🧰: Functions that are attached directly to an object or a data type (like a string, list, or custom class) and perform an action relevant to that object.

Example: Using a built-in string method.
```
phrase = "hello world"
capitalized = phrase.capitalize() # Returns "Hello world"
```

These are efficient formats for organizing and storing collections of related data.

Strings 📚: An ordered sequence of characters used to represent text. You can access individual characters by their position (index).

Example: Accessing and manipulating strings.
```
email = "test@example.com"
domain = email.split('@')[1] # Returns "example.com"
```
Lists/Arrays 🧱: An ordered, indexed collection of items. In Python, a List is dynamic and mutable. An Array is often used in other languages for a fixed-size collection of the same type.

Example: Creating and modifying a list.
```
tasks = ["buy milk", "clean", "code"]
tasks.append("sleep")   # Adds an item
print(tasks[0])         # Output: "buy milk"
```
Dictionaries/Maps 🗂️: Collections of data stored as key-value pairs. They are used for fast lookups using the unique, descriptive key instead of a numerical index.

Example: Defining and accessing a dictionary.
```
student = {
    "id": 101,
    "major": "CS",
    "gpa": 3.8
}
print(student["major"]) # Output: "CS"
```

Classes and Objects 📦: The basis of Object-Oriented Programming (OOP). A Class is a blueprint for creating things. An Object is a specific instance (a concrete item) created from that blueprint.

Example: Defining a simple class and creating an object.
```
class Pet:
    def __init__(self, name):
        self.name = name

dog = Pet("Buddy")      # 'dog' is an object of the Pet class
print(dog.name)         # Output: "Buddy"
```