what are plumbing and porcelain

Sorry for this idiot question, but I really don't know what they are and why it is necessary to distinguish between them.

On Tuesday 20 January 2009, bill lam <cbill.lam@gmail.com> wrote about 'what are plumbing and porcelain':

"plumbing" are the commands that do low-level operations. Generally, end-users won't have to use them much, if at all, but they are "fundamental" operations, upon which git is built. It's a term also used in other project some, with a similar meaning.

"porcelain" is a cute name for the end-user operations. They "cover" the plumbing to make it look and act "pretty". While some may be less useful to some users, they all are high-level operations that depend on the plumbing.

It's important to distinguish between them because we don't want the plumbing to get needlessly complex. They should be single-purpose commands and their options should be utilitarian in nature. Also, porcelain is meant to be used interactively, not in scripts, so the output or behavior might change a bit--but that is still kept to a minimum.

On Tue, 20 Jan 2009, Boyd Stephen Smith Jr. wrote:

I can see now gitk should probably be porcelain. But how about commands such as git add or git rebase used with either the -i switch on or off?

On Wednesday 21 January 2009, bill lam <cbill.lam@gmail.com> wrote about 'Re: what are plumbing and porcelain':

If you have git installed, "man git" should contain separate lists of porcelain and plumbing. If not, the documentation is available in the git repository, under Documentation/. Porcelain: cmds-mainporcelain.txt, cmds-ancillarymanipulators.txt, cmds-ancillaryinterrogators.txt, and cmds-foreignscminterface.txt. Plumbing: cmds-plumbingmanipulators.txt, cmds-plumbinginterrogators.txt, cmds-synchingrepositories.txt, cmds-synchelpers.txt, and cmds-purehelpers.txt

Thanks for bringing my attention to that.