JavaScript Core
Closures, this, prototypes, hoisting, scope
Master the fundamental building blocks of JavaScript that interviewers test most frequently. These problems cover closures, the `this` keyword, prototype chains, hoisting behavior, and scope rules. Understanding these concepts deeply is essential for senior-level frontend interviews, where you may be asked to explain or predict output from tricky code snippets.
Practice 13 interactive coding problems with step-by-step execution visualization.
Closures, this, prototypes, hoisting, scope