Python Fundamentals for a JavaScript Developer

#python #javascript #coding #100daysofcode

I'll guide you through Python fundamentals by comparing concepts with JavaScript. Let's start!

1. Hello World & Basic Syntax

JavaScript

console.log("Hello World");
let x = 5;

Python

print("Hello World")
x = 5  # No semicolon, no let/const

Key Differences:

No semicolons in Python
Indentation matters (replaces curly braces)
Comments use # instead of //

2. Variables & Data Types

JavaScript

let name = "Alice";  // string
let age = 30;        // number
let isStudent = true; // boolean
let scores = [95, 87, 91]; // array
let person = {        // object
    name: "Bob",
    age: 25
};
let nothing = null;
let notDefined = undefined;

Python

name = "Alice"        # str
age = 30              # int (or float for decimals)
is_student = True     # bool (capital T/F)
scores = [95, 87, 91] # list (mutable)
person = {            # dict (dictionary)
    "name": "Bob",
    "age": 25
}
nothing = None        # Python's null/undefined

Key Differences:

Python uses snake_case (not camelCase)
True/False capitalized
None instead of null/undefined
Lists ≈ Arrays, Dicts ≈ Objects

3. Control Flow

JavaScript

// If-else
if (age >= 18) {
    console.log("Adult");
} else if (age >= 13) {
    console.log("Teen");
} else {
    console.log("Child");
}

// For loop
for (let i = 0; i < 5; i++) {
    console.log(i);
}

// While loop
let count = 0;
while (count < 5) {
    console.log(count);
    count++;
}