The `Top' node is the node in which a reader enters an Info manual. As such, it should begin with a brief description of the manual (including the version number), and end with a master menu for the whole manual. Of course you should include any other general information you feel a reader would find helpful.
It is conventional and desirable to write an @top sectioning
command line containing the title of the document immediately after
the @node Top line (see The @top Sectioning Command).
The contents of the `Top' node should appear only in the online output;
none of it should appear in printed output, so enclose it between
@ifnottex and @end ifnottex commands. (TeX does not
print either an @node line or a menu; they appear only in Info;
strictly speaking, you are not required to enclose these parts between
@ifnottex and @end ifnottex, but it is simplest to do
so. See Conditionally Visible Text.)