For inline help, '?' is a valuable tool. A single question mark followed by the name of a function or type or statement or keyword causes the description of the identifier found in the reference manual to appear on the screen. If a list of all functions beginning with a particular string is desired, use '?^' followed by the string to match. If no match is found, the response 'No matches. Maybe try ?*<string>.' will be displayed. '?*' followed by something searches for all of its occurences in the documentation.
A query can also be started by ending a line with '?' and its modifier instead of starting it with '?'. In both cases the function 'Help' with the entered line (without the ?) as a parameter.