John Resig - How JavaScript Timers Work

How JavaScript Timers Work At a fundamental level it’s important to understand how JavaScript timers work. Often times they behave unintuitively because of the single thread which they are in. Let’s start by examining the three functions to which we have access that can construct and manipulate timers. var id = setTimeout(fn, delay); – Initiates a single timer which will call the specified function after the delay. The function returns a unique ID with which the timer can be canceled at a later time. var id = setInterval(fn, delay);

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