#### 1.3.3 The `help` function ¶

Use the `help` function to get online help. Yorick will parrot the associated `DOCUMENT` comment to your terminal:

    > #include "damped.i"
    > help, damped
      DOCUMENT damped.i --- compute and output damped sine waves
      SEE ALSO: damped_wave, q_out
    defined at:   LINE: 3  FILE: /home/icf/munro/damped.i
    >

Every Yorick function (including `help`!) has a `DOCUMENT` comment which describes what it does. Most have `SEE ALSO:` references to related help topics, so you can navigate your way through a series of related topics.

Whenever you want more details about a Yorick function, the first thing to do is to see what `help` says about it. Note that, in addition to the `DOCUMENT` comment, `help` also reports the full file name and line number where the function is defined. That way, if the comment doesn’t tell you what you need to know, you can go to the file and read the complete definition of the function.

The help for `help` itself, which is the default topic, is of particular interest, even to a Yorick expert: it tells you the directory where you can find the include files for all of Yorick’s library functions. Just type `help`, like it says when Yorick starts. One of the things you will find in Yorick’s directory tree is a `doc` directory, which contains not only the source for this manual, but also alphabetized listings of all `DOCUMENT` comments. Read the `README` file in the `doc` directory.