DateString

DateString[]
returns the current local time and date as a string.
DateString[elem]
returns the time formatted according to elems.
DateString[{e1e2, ...}]
concatinates the time formatted according to elements ei.
DateString[time]
returns the date string of an AbsoluteTime.
DateString[{ymdhms}]
returns the date string of a date list specification.
DateString[string]
returns the formatted date string of a date string specification.
DateString[specelems]
formats the time in turns of elems. Both spec and elems can take any of the above formats.

The current date and time:

Non-integer values are accepted too: