[golergka]

At least in Postgresql, it is standard practice to use timestamptz type, which saves timestamp together with a time zone. Not only it uses less space on disc, but you can do a lot of operations with it natively in database itself: sort in various ways, compare to NOW(), construct time intervals and even ensure data validity with checks.

[singron]

Timestamptz doesn't store a time zone in postgres. It converts all timestamps to utc. It's a common misconception.