JavaScript and TypeScript for Complete Beginners

Define and manage variables in JavaScript and TypeScript for complete beginners using const and let, store numbers and strings, and follow naming conventions like camelCase and PascalCase.

Explore primitive data types in JavaScript and TypeScript—numbers, strings, booleans, and union types—plus how type inference, annotations, and narrowing enforce type safety and prevent errors.

Explore the difference between undefined and null in JavaScript and TypeScript, how they represent absence or uninitialized values, and why null is generally preferred while using unions for type safety.

Discover arithmetic operators to add, subtract, multiply, and exponentiate numbers, then apply compound assignment operators to mutate variables like age and score.

Learn how if statements evaluate conditions to true or false, using if, else if, and else, and apply strict equality operators in JavaScript and TypeScript.

Explore how JavaScript treats truthy and falsy values in if statements, including non-zero numbers and non-empty strings, and learn to use explicit comparisons to avoid bugs.

Explore NaN in JavaScript, how non-numeric inputs produce not a number, and master template literals for seamless string interpolation, avoiding string concatenation pitfalls.

Explore logical operators in JavaScript and TypeScript for beginners, including not (!), and (&&), or (||), and the nullish coalescing operator (??), with explicit comparisons over truthy checks.

Define and call functions to avoid code duplication, pass inputs like radius, and return values. Learn function syntax, parameters, return types, void, and printing results with console logs.

Explore how type aliases, arrow functions, and anonymous functions work in TypeScript, including typing parameters and return types, and compare with regular JavaScript functions.

Learn how the typeof operator enables runtime type checks in JavaScript after TypeScript compilation. Apply guard clauses for early returns, avoiding nested conditionals and ensuring safer, clearer functions.

Apply type aliases, union types, and guards to implement a calculator and a number relationship checker with input validation and zero division error handling.