Namaste JavaScript — Interview Quick Notes

Ep 1–2: Execution Context & Call Stack

• Everything in JS runs inside an Execution Context — a container with two components: Memory (variable environment) and Code (thread of execution).
• JS is synchronous and single-threaded — one command at a time, in order.
• Every EC is created in two phases: Memory Creation Phase (variables → undefined, functions → full body) then Code Execution Phase (runs line by line).
• A new local EC is created each time a function is invoked and destroyed on return.
• The Call Stack manages EC creation and deletion. Also called: Program Stack, Runtime Stack, Execution Context Stack.