Merge early part of branch 'jc/fetchupload'

[git.git] / Documentation / glossary.txt

diff --git a/Documentation/glossary.txt b/Documentation/glossary.txt
index bac3c53..116ddb7 100644 (file)
--- a/Documentation/glossary.txt
+++ b/Documentation/glossary.txt
@@ -1,70 +1,61 @@
-object::
-       The unit of storage in GIT. It is uniquely identified by
-       the SHA1 of its contents. Consequently, an object can not
-       be changed.
-
-SHA1::
-       A 20-byte sequence (or 41-byte file containing the hex
-       representation and a newline). It is calculated from the
-       contents of an object by the Secure Hash Algorithm 1.
-
-object database::
-       Stores a set of "objects", and an individial object is identified
-       by its SHA1 (its ref). The objects are either stored as single
-       files, or live inside of packs.
+alternate object database::
+       Via the alternates mechanism, a repository can inherit part of its
+       object database from another object database, which is called
+       "alternate".

 
 

-object name::
-       Synonym for SHA1.
+bare repository::
+       A bare repository is normally an appropriately named
+       directory with a `.git` suffix that does not have a
+       locally checked-out copy of any of the files under revision
+       control.  That is, all of the `git` administrative and
+       control files that would normally be present in the
+       hidden `.git` sub-directory are directly present in
+       the `repository.git` directory instead, and no other files
+       are present and checked out.  Usually publishers of public
+       repositories make bare repositories available.

 
 blob object::
 
 blob object::

-       Untyped object, i.e. the contents of a file.
+       Untyped object, e.g. the contents of a file.

 
 

-tree object::
-       An object containing a list of blob and/or tree objects.
-       (A tree usually corresponds to a directory without
-       subdirectories).
-
-tree::
-       Either a working tree, or a tree object together with the
-       dependent blob and tree objects (i.e. a stored representation
-       of a working tree).
+branch::
+       A non-cyclical graph of revisions, i.e. the complete history of
+       a particular revision, which is called the branch head. The
+       branch heads are stored in `$GIT_DIR/refs/heads/`.

 
 cache::
 
 cache::

-       A collection of files whose contents are stored as objects.
-       The cache is a stored version of your working tree. Well, can
-       also contain a second, and even a third version of a working
-       tree, which are used when merging.
-
-cache entry::
-       The information regarding a particular file, stored in the index.
-       A cache entry can be unmerged, if a merge was started, but not
-       yet finished (i.e. if the cache contains multiple versions of
-       that file).
+       Obsolete for: index.

 
 

-index::
-       Contains information about the cache contents, in particular
-       timestamps and mode flags ("stat information") for the files
-       stored in the cache. An unmerged index is an index which contains
-       unmerged cache entries.
-
-working tree::
-       The set of files and directories currently being worked on.
-       Think "ls -laR"
+chain::
+       A list of objects, where each object in the list contains a
+       reference to its successor (for example, the successor of a commit
+       could be one of its parents).

 
 

-directory::
-       The list you get with "ls" :-)
+changeset::
+       BitKeeper/cvsps speak for "commit". Since git does not store
+       changes, but states, it really does not make sense to use
+       the term "changesets" with git.

 
 checkout::
        The action of updating the working tree to a revision which was
        stored in the object database.
 
 
 checkout::
        The action of updating the working tree to a revision which was
        stored in the object database.
 

-revision::
-       A particular state of files and directories which was stored in
-       the object database. It is referenced by a commit object.
+cherry-picking::
+       In SCM jargon, "cherry pick" means to choose a subset of
+       changes out of a series of changes (typically commits)
+       and record them as a new series of changes on top of
+       different codebase.  In GIT, this is performed by
+       "git cherry-pick" command to extract the change
+       introduced by an existing commit and to record it based
+       on the tip of the current branch as a new commit.
+
+clean::
+       A working tree is clean, if it corresponds to the revision
+       referenced by the current head.  Also see "dirty".

 
 commit::
 
 commit::

-       The action of storing the current state of the cache in the
+       As a verb: The action of storing the current state of the index in the

        object database. The result is a revision.
        object database. The result is a revision.

+       As a noun: Short hand for commit object.

 
 commit object::
        An object which contains the information about a particular
 
 commit object::
        An object which contains the information about a particular


@@ -72,54 +63,97 @@ commit object::
        tree object which corresponds to the top directory of the
        stored revision.
 
        tree object which corresponds to the top directory of the
        stored revision.
 

-changeset::
-       BitKeeper/cvsps speak for "commit". Since git does not store
-       changes, but states, it really does not make sense to use
-       the term "changesets" with git.
+core git::
+       Fundamental data structures and utilities of git. Exposes only
+       limited source code management tools.

 
 

-ent::
-       Favorite synonym to "tree-ish" by some total geeks.
+DAG::
+       Directed acyclic graph. The commit objects form a directed acyclic
+       graph, because they have parents (directed), and the graph of commit
+       objects is acyclic (there is no chain which begins and ends with the
+       same object).

 
 

-clean::
-       A working tree is clean, if it corresponds to the revision
-       referenced by the current head.
+dircache::
+       You are *waaaaay* behind.

 
 dirty::
        A working tree is said to be dirty if it contains modifications
        which have not been committed to the current branch.
 
 
 dirty::
        A working tree is said to be dirty if it contains modifications
        which have not been committed to the current branch.
 

+directory::
+       The list you get with "ls" :-)
+
+ent::
+       Favorite synonym to "tree-ish" by some total geeks. See
+       `http://en.wikipedia.org/wiki/Ent_(Middle-earth)` for an in-depth
+       explanation.
+
+fast forward::
+       A fast-forward is a special type of merge where you have
+       a revision and you are "merging" another branch's changes
+       that happen to be a descendant of what you have.
+       In such these cases, you do not make a new merge commit but
+       instead just update to his revision. This will happen
+       frequently on a tracking branch of a remote repository.
+
+fetch::
+       Fetching a branch means to get the branch's head ref from a
+       remote repository, to find out which objects are missing from
+       the local object database, and to get them, too.
+
+file system::
+       Linus Torvalds originally designed git to be a user space file
+       system, i.e. the infrastructure to hold files and directories.
+       That ensured the efficiency and speed of git.
+
+git archive::
+       Synonym for repository (for arch people).
+
+grafts::
+       Grafts enables two otherwise different lines of development to be
+       joined together by recording fake ancestry information for commits.
+       This way you can make git pretend the set of parents a commit
+       has is different from what was recorded when the commit was created.
+       Configured via the `.git/info/grafts` file.
+
+hash::
+       In git's context, synonym to object name.
+

 head::
        The top of a branch. It contains a ref to the corresponding
        commit object.
 
 head::
        The top of a branch. It contains a ref to the corresponding
        commit object.
 

-branch::
-       A non-cyclical graph of revisions, i.e. the complete history of
-       a particular revision, which does not (yet) have children, which
-       is called the branch head. The branch heads are stored in
-       $GIT_DIR/refs/heads/.
-
-ref::
-       A 40-byte hex representation of a SHA1 pointing to a particular
-       object. These are stored in $GIT_DIR/refs/.
-

 head ref::
        A ref pointing to a head. Often, this is abbreviated to "head".
 head ref::
        A ref pointing to a head. Often, this is abbreviated to "head".

-       Head refs are stored in $GIT_DIR/refs/heads/.
+       Head refs are stored in `$GIT_DIR/refs/heads/`.
+
+hook::
+       During the normal execution of several git commands,
+       call-outs are made to optional scripts that allow
+       a developer to add functionality or checking.
+       Typically, the hooks allow for a command to be pre-verified
+       and potentially aborted, and allow for a post-notification
+       after the operation is done.
+       The hook scripts are found in the `$GIT_DIR/hooks/` directory,
+       and are enabled by simply making them executable.

 
 

-tree-ish::
-       A ref pointing to either a commit object, a tree object, or a
-       tag object pointing to a commit or tree object.
+index::
+       A collection of files with stat information, whose contents are
+       stored as objects. The index is a stored version of your working
+       tree. Truth be told, it can also contain a second, and even a third
+       version of a working tree, which are used when merging.

 
 

-tag object::
-       An object containing a ref pointing to another object. It can
-       contain a (PGP) signature, in which case it is called "signed
-       tag object".
+index entry::
+       The information regarding a particular file, stored in the index.
+       An index entry can be unmerged, if a merge was started, but not
+       yet finished (i.e. if the index contains multiple versions of
+       that file).

 
 

-tag::
-       A ref pointing to a tag or commit object. In contrast to a head,
-       a tag is not changed by a commit. Tags (not tag objects) are
-       stored in $GIT_DIR/refs/tags/. A git tag has nothing to do with
-       a Lisp tag (which is called object type in git's context).
+master::
+       The default development branch. Whenever you create a git
+       repository, a branch named "master" is created, and becomes
+       the active branch. In most cases, this contains the local
+       development, though that is purely conventional and not required.

 
 merge::
        To merge branches means to try to accumulate the changes since a
 
 merge::
        To merge branches means to try to accumulate the changes since a


@@ -127,37 +161,65 @@ merge::
        merge uses heuristics to accomplish that. Evidently, an automatic
        merge can fail.
 
        merge uses heuristics to accomplish that. Evidently, an automatic
        merge can fail.
 

-resolve::
-       The action of fixing up manually what a failed automatic merge
-       left behind.
+object::
+       The unit of storage in git. It is uniquely identified by
+       the SHA1 of its contents. Consequently, an object can not
+       be changed.

 
 

-repository::
-       A collection of refs together with an object database containing
-       all objects, which are reachable from the refs. A repository can
-       share an object database with other repositories.
+object database::
+       Stores a set of "objects", and an individual object is identified
+       by its object name. The objects usually live in `$GIT_DIR/objects/`.

 
 

-alternate object database::
-       Via the alternates mechanism, a repository can inherit part of its
-       object database from another object database, which is called
-       "alternate".
+object identifier::
+       Synonym for object name.

 
 

-reachable::
-       An object is reachable from a ref/commit/tree/tag, if there is a
-       chain leading from the latter to the former.
+object name::
+       The unique identifier of an object. The hash of the object's contents
+       using the Secure Hash Algorithm 1 and usually represented by the 40
+       character hexadecimal encoding of the hash of the object (possibly
+       followed by a white space).

 
 

-chain::
-       A list of objects, where each object in the list contains a
-       reference to its successor (for example, the successor of a commit
-       could be one of its parents).
+object type:
+       One of the identifiers "commit","tree","tag" and "blob" describing
+       the type of an object.
+
+octopus::
+       To merge more than two branches. Also denotes an intelligent
+       predator.
+
+origin::
+       The default upstream tracking branch. Most projects have at
+       least one upstream project which they track. By default
+       'origin' is used for that purpose.  New upstream updates
+       will be fetched into this branch; you should never commit
+       to it yourself.
+
+pack::
+       A set of objects which have been compressed into one file (to save
+       space or to transmit them efficiently).
+
+pack index::
+       The list of identifiers, and other information, of the objects in a
+       pack, to assist in efficiently accessing the contents of a pack.

 
 parent::
        A commit object contains a (possibly empty) list of the logical
        predecessor(s) in the line of development, i.e. its parents.
 
 
 parent::
        A commit object contains a (possibly empty) list of the logical
        predecessor(s) in the line of development, i.e. its parents.
 

-fetch::
-       Fetching a branch means to get the branch's head ref from a
-       remote repository, to find out which objects are missing from
-       the local object database, and to get them, too.
+pickaxe::
+       The term pickaxe refers to an option to the diffcore routines
+       that help select changes that add or delete a given text string.
+       With the --pickaxe-all option, it can be used to view the
+       full changeset that introduced or removed, say, a particular
+       line of text.  See gitlink:git-diff[1].
+
+plumbing::
+       Cute name for core git.
+
+porcelain::
+       Cute name for programs and program suites depending on core git,
+       presenting a high level access to core git. Porcelains expose
+       more of a SCM interface than the plumbing.

 
 pull::
        Pulling a branch means to fetch it and merge it.
 
 pull::
        Pulling a branch means to fetch it and merge it.


@@ -171,28 +233,101 @@ push::
        the remote head ref. If the remote head is not an ancestor to the
        local head, the push fails.
 
        the remote head ref. If the remote head is not an ancestor to the
        local head, the push fails.
 

-pack::
-       A set of objects which have been compressed into one file (to save
-       space or to transmit them efficiently).
+reachable::
+       An object is reachable from a ref/commit/tree/tag, if there is a
+       chain leading from the latter to the former.

 
 

-pack index::
-       Contains offsets into a pack, so the pack can be used instead of
-       the unpacked objects.
+rebase::
+       To clean a branch by starting from the head of the main line of
+       development ("master"), and reapply the (possibly cherry-picked)
+       changes from that branch.

 
 

-plumbing::
-       Cute name for core git.
+ref::
+       A 40-byte hex representation of a SHA1 or a name that denotes
+       a particular object. These may be stored in `$GIT_DIR/refs/`.
+
+refspec::
+       A refspec is used by fetch and push to describe the mapping
+       between remote ref and local ref.  They are combined with
+       a colon in the format <src>:<dst>, preceded by an optional
+       plus sign, +.  For example:
+       `git fetch $URL refs/heads/master:refs/heads/origin`
+       means "grab the master branch head from the $URL and store
+       it as my origin branch head".
+       And `git push $URL refs/heads/master:refs/heads/to-upstream`
+       means "publish my master branch head as to-upstream master head
+       at $URL".   See also gitlink:git-push[1]

 
 

-porcelain::
-       Cute name for programs and program suites depending on core git,
-       presenting a high level access to core git. Porcelains expose
-       more of a SCM interface than the plumbing.
+repository::
+       A collection of refs together with an object database containing
+       all objects, which are reachable from the refs, possibly accompanied
+       by meta data from one or more porcelains. A repository can
+       share an object database with other repositories.

 
 

-object type:
-       One of the identifiers "commit","tree","tag" and "blob" describing
-       the type of an object.
+resolve::
+       The action of fixing up manually what a failed automatic merge
+       left behind.
+
+revision::
+       A particular state of files and directories which was stored in
+       the object database. It is referenced by a commit object.
+
+rewind::
+       To throw away part of the development, i.e. to assign the head to
+       an earlier revision.

 
 SCM::
        Source code management (tool).
 
 
 SCM::
        Source code management (tool).
 

-dircache::
-       You are *waaaaay* behind.
+SHA1::
+       Synonym for object name.
+
+topic branch::
+       A regular git branch that is used by a developer to
+       identify a conceptual line of development.  Since branches
+       are very easy and inexpensive, it is often desirable to
+       have several small branches that each contain very well
+       defined concepts or small incremental yet related changes.
+
+tracking branch::
+       A regular git branch that is used to follow changes from
+       another repository.  A tracking branch should not contain
+       direct modifications or have local commits made to it.
+       A tracking branch can usually be identified as the
+       right-hand-side ref in a Pull: refspec.
+
+tree object::
+       An object containing a list of file names and modes along with refs
+       to the associated blob and/or tree objects. A tree is equivalent
+       to a directory.
+
+tree::
+       Either a working tree, or a tree object together with the
+       dependent blob and tree objects (i.e. a stored representation
+       of a working tree).
+
+tree-ish::
+       A ref pointing to either a commit object, a tree object, or a
+       tag object pointing to a tag or commit or tree object.
+
+tag object::
+       An object containing a ref pointing to another object, which can
+       contain a message just like a commit object. It can also
+       contain a (PGP) signature, in which case it is called a "signed
+       tag object".
+
+tag::
+       A ref pointing to a tag or commit object. In contrast to a head,
+       a tag is not changed by a commit. Tags (not tag objects) are
+       stored in `$GIT_DIR/refs/tags/`. A git tag has nothing to do with
+       a Lisp tag (which is called object type in git's context).
+       A tag is most typically used to mark a particular point in the
+       commit ancestry chain.
+
+unmerged index:
+       An index which contains unmerged index entries.
+
+working tree::
+       The set of files and directories currently being worked on,
+       i.e. you can work in your working tree without using git at all.
+