org-time-stamp is an interactive compiled Lisp function in `org.el'.

(org-time-stamp ARG &optional INACTIVE)

Prompt for a date/time and insert a time stamp.
If the user specifies a time like HH:MM or if this command is
called with at least one prefix argument, the time stamp contains
the date and the time. Otherwise, only the date is be included.

All parts of a date not specified by the user is filled in from
the current date/time. So if you just press return without
typing anything, the time stamp will represent the current

If there is already a timestamp at the cursor, it will be

With two universal prefix arguments, insert an active timestamp
with the current time without prompting the user.

When called from lisp, the timestamp is inactive if INACTIVE is