@lolq9,
This format is termed as Timestamp. The Unix timestamp is a way to track time as a running total of seconds. This count starts at the Unix Epoch on January 1st, 1970 at UTC. Therefore, the Unix timestamp is merely the number of seconds between a particular date and the Unix Epoch. For more information, kindly read this Wikipedia article. In JavaScript, a timestamp is the number of milliseconds that have passed since January 1, 1970, hence you need to multiply the Unix timestamp by 1000 to convert it to JS timestamp.
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Shashi Ranjan
Team CanvasJS