How to store dates in a portable way? [duplicate]

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Does PHP time() return a GMT/UTC Timestamp?

What's the best way to manage dates across PHP, MySQL, etc?

I want to store timestamps and then format them according to say, the user's timezone preference.

But I don't fully understand what the number returned by time() is.

Does it depend on the machine's timezone config?

Should I standarize it to UTC+0 before storing it?

If I use the same unix timestamp in different machines (different time zones) and format it with date(), will I have the same time (I don't mean the same format, but the sa开发者_运维技巧me point in time)