init/Config.help

CONFIG_EXPERIMENTAL
  Some of the various things that Linux supports (such as network
  drivers, file systems, network protocols, etc.) can be in a state
  of development where the functionality, stability, or the level of
  testing is not yet high enough for general use. This is usually
  known as the "alpha-test" phase among developers. If a feature is
  currently in alpha-test, then the developers usually discourage
  uninformed widespread use of this feature by the general public to
  avoid "Why doesn't this work?" type mail messages. However, active
  testing and use of these systems is welcomed. Just be aware that it
  may not meet the normal level of reliability or it may fail to work
  in some special cases. Detailed bug reports from people familiar
  with the kernel internals are usually welcomed by the developers
  (before submitting bug reports, please read the documents
  <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
  <file:Documentation/BUG-HUNTING>, and
  <file:Documentation/oops-tracing.txt> in the kernel source).

  This option will also make obsoleted drivers available. These are
  drivers that have been replaced by something else, and/or are
  scheduled to be removed in a future kernel release.

  Unless you intend to help test and develop a feature or driver that
  falls into this category, or you have a situation that requires
  using these features, you should probably say N here, which will
  cause the configurator to present you with fewer choices. If
  you say Y here, you will be offered the choice of using features or
  drivers that are currently considered to be in the alpha-test phase.

CONFIG_NET
  Unless you really know what you are doing, you should say Y here.
  The reason is that some programs need kernel networking support even
  when running on a stand-alone machine that isn't connected to any
  other computer. If you are upgrading from an older kernel, you
  should consider updating your networking tools too because changes
  in the kernel and the tools often go hand in hand. The tools are
  contained in the package net-tools, the location and version number
  of which are given in <file:Documentation/Changes>.

  For a general introduction to Linux networking, it is highly
  recommended to read the NET-HOWTO, available from
  <http://www.linuxdoc.org/docs.html#howto>.

CONFIG_SYSVIPC
  Inter Process Communication is a suite of library functions and
  system calls which let processes (running programs) synchronize and
  exchange information. It is generally considered to be a good thing,
  and some programs won't run unless you say Y here. In particular, if
  you want to run the DOS emulator dosemu under Linux (read the
  DOSEMU-HOWTO, available from
  <http://www.linuxdoc.org/docs.html#howto>), you'll need to say Y
  here.

  You can find documentation about IPC with "info ipc" and also in
  section 6.4 of the Linux Programmer's Guide, available from
  <http://www.linuxdoc.org/docs.html#guide>.

CONFIG_BSD_PROCESS_ACCT
  If you say Y here, a user level program will be able to instruct the
  kernel (via a special system call) to write process accounting
  information to a file: whenever a process exits, information about
  that process will be appended to the file by the kernel.  The
  information includes things such as creation time, owning user,
  command name, memory usage, controlling terminal etc. (the complete
  list is in the struct acct in <file:include/linux/acct.h>).  It is
  up to the user level program to do useful things with this
  information.  This is generally a good idea, so say Y.

CONFIG_SYSCTL
  The sysctl interface provides a means of dynamically changing
  certain kernel parameters and variables on the fly without requiring
  a recompile of the kernel or reboot of the system.  The primary
  interface consists of a system call, but if you say Y to "/proc
  file system support", a tree of modifiable sysctl entries will be
  generated beneath the /proc/sys directory. They are explained in the
  files in <file:Documentation/sysctl/>.  Note that enabling this
  option will enlarge the kernel by at least 8 KB.

  As it is generally a good thing, you should say Y here unless
  building a kernel for install/rescue disks or your system is very
  limited in memory.

CONFIG_MODULES
  Kernel modules are small pieces of compiled code which can be
  inserted in or removed from the running kernel, using the programs
  insmod and rmmod. This is described in the file
  <file:Documentation/modules.txt>, including the fact that you have
  to say "make modules" in order to compile the modules that you chose
  during kernel configuration.  Modules can be device drivers, file
  systems, binary executable formats, and so on. If you think that you
  may want to make use of modules with this kernel in the future, then
  say Y here.  If unsure, say Y.

CONFIG_MODVERSIONS
  Usually, modules have to be recompiled whenever you switch to a new
  kernel.  Saying Y here makes it possible, and safe, to use the
  same modules even after compiling a new kernel; this requires the
  program modprobe. All the software needed for module support is in
  the modutils package (check the file <file:Documentation/Changes>
  for location and latest version).  NOTE: if you say Y here but don't
  have the program genksyms (which is also contained in the above
  mentioned modutils package), then the building of your kernel will
  fail.  If you are going to use modules that are generated from
  non-kernel sources, you would benefit from this option.  Otherwise
  it's not that important.  So, N ought to be a safe bet.

CONFIG_KMOD
  Normally when you have selected some drivers and/or file systems to
  be created as loadable modules, you also have the responsibility to
  load the corresponding modules (using the programs insmod or
  modprobe) before you can use them. If you say Y here however, the
  kernel will be able to load modules for itself: when a part of the
  kernel needs a module, it runs modprobe with the appropriate
  arguments, thereby loading the module if it is available. (This is a
  replacement for kerneld.) Say Y here and read about configuring it
  in <file:Documentation/kmod.txt>.