Help Lookup is available through the
Mathematica code popup.
It allows you to look up help for Mathematica
functions on the Wolfram Research web site. Select the name of a function
that appears in your code.
Pull down the menu and choose
A web browser is opened that shows
the result of the result of the search on the Wolfram Research site.
From this you can follow links to get more detailed information
about the function.