10.B: 
  man -k 
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When you say
 > man command man command:
> man man  
  
NAME
- man - Displays reference pages 
  
  
SYNOPSIS
 man [-] [-M|-P pathname] [-t] [ section[suffix]]
 title 
   man [-M | -P pathname] -k keyword 
  
  
DESCRIPTION
 The man command provides reference information on topics, such as 
commands, subroutines, and files.  The man command provides one-line 
descriptions of commands specified by name.  The man command also provides 
information on all commands whose descriptions contain a set of 
user-specified keywords.    Inevitably, sometimes you'll feel that man gives too much information, other times you'll feel like there is not enough. However, the example at the end of the man page often tell you what you need to know. In any case, it works for most every command and is perfectly convenient.
The thoughtful reader may be saying to herself, "a lot of
good man is, how do you expect me to remember all 
those non English command names?" Here again, Unix's good nature comes through, and 
provides the man -k form to help (and discussed in the 
next section).
  10.B: 
  man -k 
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