:os.timestamp                   # => {MegaSecs, Secs, MicroSecs}
:erlang.time                    # => {Hour, Minute, Second}
:erlang.date                    # => {Year, Month, Day}
:erlang.localtime               # => {{Year, Month, Day}, {Hour, Minute, Second}}
:erlang.universaltime           # => {{Year, Month, Day}, {Hour, Minute, Second}}

:calendar.local_time            # => {{Year, Month, Day}, {Hour, Minute, Second}}
:calendar.universal_time        # => {{Year, Month, Day}, {Hour, Minute, Second}}