JavaScript Interview Prep: Core Fundamentals and Data Types Explained

A DEV Community article kicks off an 8-part series aimed at developers preparing for JavaScript technical interviews. The first installment focuses on foundational concepts that interviewers commonly use to assess genuine language understanding beyond syntax memorization. Topics covered include JavaScript's seven primitive types, the distinction between null and undefined, strict versus loose equality, type coercion, and hoisting behavior. The guide also explains variable declaration differences between var, let, and const, including scoping rules and the Temporal Dead Zone. The series will continue with functions, scope, and closures in its next part.