Study guide · 7 topics
TypeScript Exam Study Guide
Seven topic guides covering everything tested on TypeScript interviews and exams. Code examples, exam traps, and tips throughout.
Test your TypeScript knowledge → Free · No sign-upTypeScript Types vs Interfaces — When to Use Which
Types and interfaces are the foundation of TypeScript. Here's what exams test — the differences and when each applies.
Read guide →02 · 4 min readTypeScript Type Inference Explained — When to Add Type Annotations
TypeScript infers most types automatically. Here's when you need annotations and when they just add noise.
Read guide →03 · 6 min readTypeScript Union & Intersection Types — Discriminated Unions Explained
Union and intersection types model "or" and "and" relationships. Discriminated unions are the most powerful pattern.
Read guide →04 · 6 min readTypeScript Generics Explained — Generic Functions, Constraints & keyof
Generics enable reusable, type-safe code. Here's what interviews test — from basic generic functions to constraints.
Read guide →05 · 5 min readTypeScript Utility Types — Partial, Required, Pick, Omit, Record
Utility types transform existing types into new ones. These save you from writing repetitive type definitions.
Read guide →06 · 5 min readTypeScript Pick and Omit Utility Types — With Examples 2026
Pick selects a subset of properties from a type. Omit excludes specific properties. Both are essential for shaping types without duplication.
Read guide →07 · 5 min readTypeScript Type Narrowing — typeof, instanceof, Custom Type Guards
TypeScript narrows union types inside conditional blocks. Here's all the narrowing patterns and custom type guards.
Read guide →Where TypeScript leads
Certifications that build on TypeScript
Real proctored exams with published blueprints — each with a free readiness test here that scores you per exam domain rather than giving you one number.
GitHub GH-600 (Agentic AI Developer)
Microsoft lists Developer among GH-600’s roles and asks for experience with the SDLC, GitHub workflows and code review. The exam tests running coding agents on a real repository, not a language.