string, number, boolean and type inference.
✍️ 3 exercises + code challenge in this lessonThe basic types are string, number and boolean.
let age: number = 25;let city = "Lahore"; — TypeScript knows it is a string.Assigning the wrong type is a compile error: age = "old"; fails.
any turns type checking off (avoid it).unknown is a safe "any": you must check the type before use.never is for values that never happen.Mastering TypeScript Simple Types helps you write clean and reliable TypeScript code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
let age: number = 25;
let city = "Lahore"; // inferred as string
let active: boolean = true;
age = age + 1;
console.log(age, city, active);26 Lahore true
Check what you learned in “TypeScript Simple Types”.
Declare a boolean variable.
let isOpen: = true;
Which type is a safe alternative to any?
Declare price: number = 1500 and qty: number = 3, then log their product.
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