What is a 'system account file'?

[Dan Radu Dragomir]

Detlef Lechner wrote:
> Hello Avi,
>
> On Thu, 2010-02-11 at 12:23 +0000, Avi Greenbury wrote:
>   
>> Detlef Lechner wrote:
>>     
>
>   
>>> man usermod: "DESCRIPTION: The usermod command modifies the system
>>> account files to reflect the changes that are specified on the command
>>> line." 
>>>       
>> ... 
>>     
>>> What is a 'system account file'?
>>>       
>> There's three, as pertaining to users, generally:
>>
>> /etc/passwd	user configuration
>> /etc/groups	group configuration
>> /etc/shadow	user passwords
>> /etc/gshadow	secure group configuration
>>
>> There's more info here:
>> http://www.redhat.com/docs/manuals/linux/RHL-8.0-Manual/admin-primer/s1-acctsgrps-files.html
>>     
>
> I believe that your answer only partially meets my question. For
> example,
> why does Ubuntu consider it necessary to create a user account named
> kernoops (which it does in /etc/passwd)?
>
> Regards,
> Detlef
>   
Since you asked that question i think it's safe to assume you are 
talking about ubuntu server, the user kernoops being the user under 
which the package kerneloops is running (nice app also :P)

Regards,
Dan