Merge branch 'fix'

[git.git] / Documentation / glossary.txt

diff --git a/Documentation/glossary.txt b/Documentation/glossary.txt
index bac3c53..02a9d9c 100644 (file)
--- a/Documentation/glossary.txt
+++ b/Documentation/glossary.txt
@@ -1,70 +1,83 @@
 object::
 object::

-       The unit of storage in GIT. It is uniquely identified by
+       The unit of storage in git. It is uniquely identified by

        the SHA1 of its contents. Consequently, an object can not
        be changed.
 
        the SHA1 of its contents. Consequently, an object can not
        be changed.
 

+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).
+

 SHA1::
 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.
+       Synonym for object name.

 
 

-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.
+object identifier::
+       Synonym for object name.

 
 

-object name::
-       Synonym for SHA1.
+hash::
+       In git's context, synonym to object name.
+
+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/`.

 
 blob object::
 
 blob object::

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

 
 tree object::
 
 tree object::

-       An object containing a list of blob and/or tree objects.
-       (A tree usually corresponds to a directory without
-       subdirectories).
+       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::
        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).
 

-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.
+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).
+
+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.

 
 

-cache entry::
+index entry::

        The information regarding a particular file, stored in the index.
        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
+       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).
 
        that file).
 

-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.
+unmerged index:
+       An index which contains unmerged index entries.
+
+cache::
+       Obsolete for: index.

 
 working tree::
 
 working tree::

-       The set of files and directories currently being worked on.
-       Think "ls -laR"
+       The set of files and directories currently being worked on,
+       i.e. you can work in your working tree without using git at all.

 
 directory::
        The list you get with "ls" :-)
 
 
 directory::
        The list you get with "ls" :-)
 

-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.
 
 revision::
        A particular state of files and directories which was stored in
        the object database. It is referenced by a commit object.
 

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

 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


@@ -72,14 +85,15 @@ 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.
 

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

 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.
 
 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.
 

-ent::
-       Favorite synonym to "tree-ish" by some total geeks.
-

 clean::
        A working tree is clean, if it corresponds to the revision
        referenced by the current head.
 clean::
        A working tree is clean, if it corresponds to the revision
        referenced by the current head.


@@ -94,32 +108,50 @@ head::
 
 branch::
        A non-cyclical graph of revisions, i.e. the complete history of
 
 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
-       $GIT_DIR/refs/heads/.
+       a particular revision, which is called the branch head. The
+       branch heads are stored in `$GIT_DIR/refs/heads/`.
+
+master::
+       The default 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.
+
+origin::
+       The default upstream branch. Most projects have one upstream
+       project which they track, and by default 'origin' is used for
+       that purpose.  New updates from upstream will be fetched into
+       this branch; you should never commit to it yourself.

 
 ref::
        A 40-byte hex representation of a SHA1 pointing to a particular
 
 ref::
        A 40-byte hex representation of a SHA1 pointing to a particular

-       object. These are stored in $GIT_DIR/refs/.
+       object. These may be stored in `$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/`.

 
 tree-ish::
        A ref pointing to either a commit object, a tree object, or a
 
 tree-ish::
        A ref pointing to either a commit object, a tree object, or a

-       tag object pointing to a commit or tree object.
+       tag object pointing to a tag or commit or tree object.
+
+ent::
+       Favorite synonym to "tree-ish" by some total geeks. See
+       `http://en.wikipedia.org/wiki/Ent_(Middle-earth)` for an in-depth
+       explanation.

 
 tag object::
 
 tag object::

-       An object containing a ref pointing to another object. It can
-       contain a (PGP) signature, in which case it is called "signed
+       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
        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 $GIT_DIR/refs/tags/. A git tag has nothing to do with
+       stored in `$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 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.

 
 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


@@ -127,15 +159,37 @@ 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.
 

+octopus::
+       To merge more than two branches. Also denotes an intelligent
+       predator.
+

 resolve::
        The action of fixing up manually what a failed automatic merge
        left behind.
 
 resolve::
        The action of fixing up manually what a failed automatic merge
        left behind.
 

+rewind::
+       To throw away part of the development, i.e. to assign the head to
+       an earlier revision.
+
+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.
+

 repository::
        A collection of refs together with an object database containing
 repository::
        A collection of refs together with an object database containing

-       all objects, which are reachable from the refs. A repository can
+       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.
 
        share an object database with other repositories.
 

+git archive::
+       Synonym for repository (for arch people).
+
+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.
+

 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 database::
        Via the alternates mechanism, a repository can inherit part of its
        object database from another object database, which is called


@@ -150,10 +204,6 @@ chain::
        reference to its successor (for example, the successor of a commit
        could be one of its parents).
 
        reference to its successor (for example, the successor of a commit
        could be one of 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
 fetch::
        Fetching a branch means to get the branch's head ref from a
        remote repository, to find out which objects are missing from


@@ -176,8 +226,12 @@ pack::
        space or to transmit them efficiently).
 
 pack index::
        space or to transmit them efficiently).
 
 pack index::

-       Contains offsets into a pack, so the pack can be used instead of
-       the unpacked objects.
+       The list of identifiers, and other information, of the objects in a
+       pack, to assist in efficiently accessing the contents of a pack. 
+
+core git::
+       Fundamental data structures and utilities of git. Exposes only
+       limited source code management tools.

 
 plumbing::
        Cute name for core git.
 
 plumbing::
        Cute name for core git.


@@ -196,3 +250,4 @@ SCM::
 
 dircache::
        You are *waaaaay* behind.
 
 dircache::
        You are *waaaaay* behind.

+