JavaScript Execution Context and the Call Stack Explained Simply

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JavaScript creates an 'execution context' each time code runs — one globally at program start and a new one for every function call. These contexts store variables, functions, and other necessary information needed to execute code successfully. All active contexts are managed through a call stack, a Last-In-First-Out data structure where contexts are added and removed as functions start and finish. Each execution context goes through two phases: a creation phase, where memory is prepared and variables are registered, and an execution phase, where code runs line by line. This two-phase process gives rise to hoisting, where variable and function declarations are processed before execution begins, with key differences in behavior between var, let, and const.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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