RE: protection against buffer overflows

[Steve Johnson]

this may seem trivial but i've never really understood how a buffer
overflow happens and effects your system, i have some knowledge of 
programming, but not much at low levels.  like dealing direct with
memory or devices(other than using standard pointers and reading and
writing to devices thruough file pointers).  anyone to offer any
explanation will be showered with greatness!
thanks,
steve