Skip to content
Interview Prep Buddy LogoInterview Prep Buddy

Execution Context

Execution Context

Section titled “Execution Context”

Introduction

Section titled “Introduction”

An execution context is the environment where JavaScript code is evaluated and executed. Every time a function is called, a new execution context is created.

Learning Objectives

Section titled “Learning Objectives”
  • Understand the three types of execution context (global, function, eval)
  • Learn the two phases: creation and execution
  • Understand the lexical environment and variable environment
  • Know how execution contexts are pushed/popped from the call stack

Visual Summary

Section titled “Visual Summary”
flowchart TD
    A["JavaScript Engine Starts"]
    B["Global Execution Context Created"]
    C["Phase 1: Creation (Memory)"]
    D["Phase 2: Execution"]
    E["Function Call Detected"]
    F["New Function Execution Context"]
    G["Repeat Creation & Execution"]
    H["Function Returns → Context Popped"]


    A --> B --> C --> D
    D --> E --> F --> G --> H
    H --> D

Topics Covered

Section titled “Topics Covered”
TopicDescriptionEst. Time
Types of ContextGlobal, function, and eval contexts10 min
Creation PhaseMemory allocation, hoisting, scope setup15 min
Execution PhaseCode execution, variable assignment10 min
Lexical EnvironmentEnvironment records, scope chain15 min

Prerequisites

Section titled “Prerequisites”
  • Basic JavaScript syntax
  • Functions and scope
  • Hoisting basics

Learning Path

Section titled “Learning Path”
Types of Context → Creation Phase → Execution Phase → Lexical Environment
Section titled “Related Topics”