How Javascript Works

Everything in javascript happens  inside Execution Context .

Execution  Context  is like a big box. It has memory(variable environment) and code(thread of Execution  ).

memory stores all variable and functions in key value pair form . 

and on thread code is executed line by  line.

javascript is synchronous single threaded language . It means javascript can execute one command at a time in specific  order. it will only go to next line once the current command is executed .


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