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TypeScript fundamentals, static typing, interfaces, generics, advanced types, tooling, and large-scale application development.
May 30, 2026
Learn TypeScript fundamentals, static typing, interfaces, functions, and why TypeScript has become the standard for modern JavaScript development.
June 10, 2026
TypeScript Fundamentals: Why JavaScript Developers Need Types Introduction JavaScript is one of the most successful programming languages ever created. It powers websites, backend servers, desktop applications, mobile applications, and even cloud infrastructure. However, JavaScript was originally designed as a scripting language for browsers. As applications became larger and more complex, developers began encountering problems that JavaScript could not detect before the code was executed. To solve these problems, Microsoft created TypeScript. TypeScript Is a Superset of JavaScript TypeScript builds on top of JavaScript. Every valid JavaScript program is also valid TypeScript. TypeScript does not replace JavaScript. Instead, it extends JavaScript by adding a static type system and better tooling. Some Strange JavaScript Behaviors These behaviors are legal JavaScript, but they can become problematic in large applications. TypeScript Adds Types A type describes what kind of value a variable can store. Static Type Checking TypeScript performs static type checking before code executes. This allows many errors to be detected during development rather than at runtime. Browsers Cannot Execute TypeScript Browsers understand JavaScript, not TypeScript. TypeScript must be transpiled into JavaScript before execution. Installing TypeScript This provides the TypeScript compiler: Compiling TypeScript The compiler generates an app.js file. TypeScript Playground The TypeScript Playground provides an online environment where you can experiment with TypeScript and inspect the generated JavaScript. Summary TypeScript is JavaScript with an additional type system. It helps developers catch mistakes before runtime and makes large applications easier to maintain.
June 10, 2026
TypeScript Types, Inference and Functions Primitive Types TypeScript provides several built-in primitive types. Type Inference TypeScript often figures out types automatically. This process is called type inference. Better Editor Support Because TypeScript knows the type of a variable, editors can provide autocomplete and intelligent suggestions. Compilation Still Happens With Errors TypeScript reports an error, but JavaScript can still be generated depending on compiler settings. The Any Type The any type disables type checking. Implicit Any When TypeScript cannot determine a type, it may infer any. Function Parameters Return Types Default Parameters Void Contextual Typing TypeScript infers that color is a string. Never A function returning never never successfully completes. Summary Type inference, function typing, any, void, and never form the foundation of everyday TypeScript development.
June 10, 2026
TypeScript Objects, Arrays, Unions and Tuples Object Types Excess Property Checks TypeScript reports an error for excess properties when passed inline. Type Aliases Nested Types Optional Properties Readonly Properties Intersection Types Array Types Union Types Type Narrowing Union Arrays Literal Types Tuples React and Tuples Tuples are commonly used in React hooks. Tuples vs Objects Objects are often easier to understand because property names provide context, while tuples rely on position. Enums JavaScript does not have built-in enums. TypeScript adds enums as a way to group related named constants together. Key Points Enum names and members are commonly capitalized. Numeric enums start at 0 by default. Subsequent values are automatically incremented. You can also assign values explicitly. Enums and Databases When persisted, the value stored is: not: String Enums String enums are often preferred for database storage because they are readable and stable. Mixed Enums Mixed enums are valid but rarely used. Enums vs Objects Enums provide organization, autocomplete support, readability, and type safety. Many modern TypeScript projects also use as const objects as an alternative. Summary Objects, arrays, unions, intersections, tuples, and enums are fundamental building blocks for modeling data in TypeScript.