Question 1

What is Unix Timestamp?

Accepted Answer

A Unix timestamp is the number of seconds (or milliseconds in JavaScript) elapsed since the Unix Epoch: January 1, 1970, 00:00:00 UTC. It is the universal time representation in programming — unambiguous, timezone-independent, and easily arithmetic-operable.

Question 2

What is the Year 2038 problem?

Accepted Answer

32-bit signed integers max out at 2,147,483,647 — representing January 19, 2038, at 03:14:07 UTC. Systems using 32-bit timestamps will overflow and roll over to negative values (1901), causing date calculation errors. Modern systems and languages use 64-bit timestamps, which won't overflow for ~292 billion years.

Question 3

How do I convert a Unix timestamp to a human-readable date in JavaScript?

Accepted Answer

new Date(timestamp * 1000).toLocaleString() for seconds-based timestamps (multiply by 1000 to convert to milliseconds). new Date(timestamp).toISOString() for milliseconds-based. Use Intl.DateTimeFormat for locale-aware formatting.

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