7f87f560c89c74c99444bd75b15fda5f2d8bdc76
   1[[def_alternate_object_database]]alternate object database::
   2        Via the alternates mechanism, a <<def_repository,repository>>
   3        can inherit part of its <<def_object_database,object database>>
   4        from another object database, which is called "alternate".
   5
   6[[def_bare_repository]]bare repository::
   7        A bare repository is normally an appropriately
   8        named <<def_directory,directory>> with a `.git` suffix that does not
   9        have a locally checked-out copy of any of the files under
  10        revision control. That is, all of the Git
  11        administrative and control files that would normally be present in the
  12        hidden `.git` sub-directory are directly present in the
  13        `repository.git` directory instead,
  14        and no other files are present and checked out. Usually publishers of
  15        public repositories make bare repositories available.
  16
  17[[def_blob_object]]blob object::
  18        Untyped <<def_object,object>>, e.g. the contents of a file.
  19
  20[[def_branch]]branch::
  21        A "branch" is an active line of development.  The most recent
  22        <<def_commit,commit>> on a branch is referred to as the tip of
  23        that branch.  The tip of the branch is referenced by a branch
  24        <<def_head,head>>, which moves forward as additional development
  25        is done on the branch.  A single Git
  26        <<def_repository,repository>> can track an arbitrary number of
  27        branches, but your <<def_working_tree,working tree>> is
  28        associated with just one of them (the "current" or "checked out"
  29        branch), and <<def_HEAD,HEAD>> points to that branch.
  30
  31[[def_cache]]cache::
  32        Obsolete for: <<def_index,index>>.
  33
  34[[def_chain]]chain::
  35        A list of objects, where each <<def_object,object>> in the list contains
  36        a reference to its successor (for example, the successor of a
  37        <<def_commit,commit>> could be one of its <<def_parent,parents>>).
  38
  39[[def_changeset]]changeset::
  40        BitKeeper/cvsps speak for "<<def_commit,commit>>". Since Git does not
  41        store changes, but states, it really does not make sense to use the term
  42        "changesets" with Git.
  43
  44[[def_checkout]]checkout::
  45        The action of updating all or part of the
  46        <<def_working_tree,working tree>> with a <<def_tree_object,tree object>>
  47        or <<def_blob_object,blob>> from the
  48        <<def_object_database,object database>>, and updating the
  49        <<def_index,index>> and <<def_HEAD,HEAD>> if the whole working tree has
  50        been pointed at a new <<def_branch,branch>>.
  51
  52[[def_cherry-picking]]cherry-picking::
  53        In <<def_SCM,SCM>> jargon, "cherry pick" means to choose a subset of
  54        changes out of a series of changes (typically commits) and record them
  55        as a new series of changes on top of a different codebase. In Git, this is
  56        performed by the "git cherry-pick" command to extract the change introduced
  57        by an existing <<def_commit,commit>> and to record it based on the tip
  58        of the current <<def_branch,branch>> as a new commit.
  59
  60[[def_clean]]clean::
  61        A <<def_working_tree,working tree>> is clean, if it
  62        corresponds to the <<def_revision,revision>> referenced by the current
  63        <<def_head,head>>. Also see "<<def_dirty,dirty>>".
  64
  65[[def_commit]]commit::
  66        As a noun: A single point in the
  67        Git history; the entire history of a project is represented as a
  68        set of interrelated commits.  The word "commit" is often
  69        used by Git in the same places other revision control systems
  70        use the words "revision" or "version".  Also used as a short
  71        hand for <<def_commit_object,commit object>>.
  72+
  73As a verb: The action of storing a new snapshot of the project's
  74state in the Git history, by creating a new commit representing the current
  75state of the <<def_index,index>> and advancing <<def_HEAD,HEAD>>
  76to point at the new commit.
  77
  78[[def_commit_object]]commit object::
  79        An <<def_object,object>> which contains the information about a
  80        particular <<def_revision,revision>>, such as <<def_parent,parents>>, committer,
  81        author, date and the <<def_tree_object,tree object>> which corresponds
  82        to the top <<def_directory,directory>> of the stored
  83        revision.
  84
  85[[def_core_git]]core Git::
  86        Fundamental data structures and utilities of Git. Exposes only limited
  87        source code management tools.
  88
  89[[def_DAG]]DAG::
  90        Directed acyclic graph. The <<def_commit_object,commit objects>> form a
  91        directed acyclic graph, because they have parents (directed), and the
  92        graph of commit objects is acyclic (there is no <<def_chain,chain>>
  93        which begins and ends with the same <<def_object,object>>).
  94
  95[[def_dangling_object]]dangling object::
  96        An <<def_unreachable_object,unreachable object>> which is not
  97        <<def_reachable,reachable>> even from other unreachable objects; a
  98        dangling object has no references to it from any
  99        reference or <<def_object,object>> in the <<def_repository,repository>>.
 100
 101[[def_detached_HEAD]]detached HEAD::
 102        Normally the <<def_HEAD,HEAD>> stores the name of a
 103        <<def_branch,branch>>.  However, Git also allows you to <<def_checkout,check out>>
 104        an arbitrary <<def_commit,commit>> that isn't necessarily the tip of any
 105        particular branch.  In this case HEAD is said to be "detached".
 106
 107[[def_directory]]directory::
 108        The list you get with "ls" :-)
 109
 110[[def_dirty]]dirty::
 111        A <<def_working_tree,working tree>> is said to be "dirty" if
 112        it contains modifications which have not been <<def_commit,committed>> to the current
 113        <<def_branch,branch>>.
 114
 115[[def_evil_merge]]evil merge::
 116        An evil merge is a <<def_merge,merge>> that introduces changes that
 117        do not appear in any <<def_parent,parent>>.
 118
 119[[def_fast_forward]]fast-forward::
 120        A fast-forward is a special type of <<def_merge,merge>> where you have a
 121        <<def_revision,revision>> and you are "merging" another
 122        <<def_branch,branch>>'s changes that happen to be a descendant of what
 123        you have. In such these cases, you do not make a new <<def_merge,merge>>
 124        <<def_commit,commit>> but instead just update to his
 125        revision. This will happen frequently on a
 126        <<def_remote_tracking_branch,remote-tracking branch>> of a remote
 127        <<def_repository,repository>>.
 128
 129[[def_fetch]]fetch::
 130        Fetching a <<def_branch,branch>> means to get the
 131        branch's <<def_head_ref,head ref>> from a remote
 132        <<def_repository,repository>>, to find out which objects are
 133        missing from the local <<def_object_database,object database>>,
 134        and to get them, too.  See also linkgit:git-fetch[1].
 135
 136[[def_file_system]]file system::
 137        Linus Torvalds originally designed Git to be a user space file system,
 138        i.e. the infrastructure to hold files and directories. That ensured the
 139        efficiency and speed of Git.
 140
 141[[def_git_archive]]Git archive::
 142        Synonym for <<def_repository,repository>> (for arch people).
 143
 144[[def_gitfile]]gitfile::
 145        A plain file `.git` at the root of a working tree that
 146        points at the directory that is the real repository.
 147
 148[[def_grafts]]grafts::
 149        Grafts enables two otherwise different lines of development to be joined
 150        together by recording fake ancestry information for commits. This way
 151        you can make Git pretend the set of <<def_parent,parents>> a <<def_commit,commit>> has
 152        is different from what was recorded when the commit was
 153        created. Configured via the `.git/info/grafts` file.
 154
 155[[def_hash]]hash::
 156        In Git's context, synonym for <<def_object_name,object name>>.
 157
 158[[def_head]]head::
 159        A <<def_ref,named reference>> to the <<def_commit,commit>> at the tip of a
 160        <<def_branch,branch>>.  Heads are stored in a file in
 161        `$GIT_DIR/refs/heads/` directory, except when using packed refs. (See
 162        linkgit:git-pack-refs[1].)
 163
 164[[def_HEAD]]HEAD::
 165        The current <<def_branch,branch>>.  In more detail: Your <<def_working_tree,
 166        working tree>> is normally derived from the state of the tree
 167        referred to by HEAD.  HEAD is a reference to one of the
 168        <<def_head,heads>> in your repository, except when using a
 169        <<def_detached_HEAD,detached HEAD>>, in which case it directly
 170        references an arbitrary commit.
 171
 172[[def_head_ref]]head ref::
 173        A synonym for <<def_head,head>>.
 174
 175[[def_hook]]hook::
 176        During the normal execution of several Git commands, call-outs are made
 177        to optional scripts that allow a developer to add functionality or
 178        checking. Typically, the hooks allow for a command to be pre-verified
 179        and potentially aborted, and allow for a post-notification after the
 180        operation is done. The hook scripts are found in the
 181        `$GIT_DIR/hooks/` directory, and are enabled by simply
 182        removing the `.sample` suffix from the filename. In earlier versions
 183        of Git you had to make them executable.
 184
 185[[def_index]]index::
 186        A collection of files with stat information, whose contents are stored
 187        as objects. The index is a stored version of your
 188        <<def_working_tree,working tree>>. Truth be told, it can also contain a second, and even
 189        a third version of a working tree, which are used
 190        when <<def_merge,merging>>.
 191
 192[[def_index_entry]]index entry::
 193        The information regarding a particular file, stored in the
 194        <<def_index,index>>. An index entry can be unmerged, if a
 195        <<def_merge,merge>> was started, but not yet finished (i.e. if
 196        the index contains multiple versions of that file).
 197
 198[[def_master]]master::
 199        The default development <<def_branch,branch>>. Whenever you
 200        create a Git <<def_repository,repository>>, a branch named
 201        "master" is created, and becomes the active branch. In most
 202        cases, this contains the local development, though that is
 203        purely by convention and is not required.
 204
 205[[def_merge]]merge::
 206        As a verb: To bring the contents of another
 207        <<def_branch,branch>> (possibly from an external
 208        <<def_repository,repository>>) into the current branch.  In the
 209        case where the merged-in branch is from a different repository,
 210        this is done by first <<def_fetch,fetching>> the remote branch
 211        and then merging the result into the current branch.  This
 212        combination of fetch and merge operations is called a
 213        <<def_pull,pull>>.  Merging is performed by an automatic process
 214        that identifies changes made since the branches diverged, and
 215        then applies all those changes together.  In cases where changes
 216        conflict, manual intervention may be required to complete the
 217        merge.
 218+
 219As a noun: unless it is a <<def_fast_forward,fast-forward>>, a
 220successful merge results in the creation of a new <<def_commit,commit>>
 221representing the result of the merge, and having as
 222<<def_parent,parents>> the tips of the merged <<def_branch,branches>>.
 223This commit is referred to as a "merge commit", or sometimes just a
 224"merge".
 225
 226[[def_object]]object::
 227        The unit of storage in Git. It is uniquely identified by the
 228        <<def_SHA1,SHA-1>> of its contents. Consequently, an
 229        object can not be changed.
 230
 231[[def_object_database]]object database::
 232        Stores a set of "objects", and an individual <<def_object,object>> is
 233        identified by its <<def_object_name,object name>>. The objects usually
 234        live in `$GIT_DIR/objects/`.
 235
 236[[def_object_identifier]]object identifier::
 237        Synonym for <<def_object_name,object name>>.
 238
 239[[def_object_name]]object name::
 240        The unique identifier of an <<def_object,object>>.  The
 241        object name is usually represented by a 40 character
 242        hexadecimal string.  Also colloquially called <<def_SHA1,SHA-1>>.
 243
 244[[def_object_type]]object type::
 245        One of the identifiers "<<def_commit_object,commit>>",
 246        "<<def_tree_object,tree>>", "<<def_tag_object,tag>>" or
 247        "<<def_blob_object,blob>>" describing the type of an
 248        <<def_object,object>>.
 249
 250[[def_octopus]]octopus::
 251        To <<def_merge,merge>> more than two <<def_branch,branches>>.
 252
 253[[def_origin]]origin::
 254        The default upstream <<def_repository,repository>>. Most projects have
 255        at least one upstream project which they track. By default
 256        'origin' is used for that purpose. New upstream updates
 257        will be fetched into remote <<def_remote_tracking_branch,remote-tracking branches>> named
 258        origin/name-of-upstream-branch, which you can see using
 259        `git branch -r`.
 260
 261[[def_pack]]pack::
 262        A set of objects which have been compressed into one file (to save space
 263        or to transmit them efficiently).
 264
 265[[def_pack_index]]pack index::
 266        The list of identifiers, and other information, of the objects in a
 267        <<def_pack,pack>>, to assist in efficiently accessing the contents of a
 268        pack.
 269
 270[[def_pathspec]]pathspec::
 271       Pattern used to specify paths.
 272+
 273Pathspecs are used on the command line of "git ls-files", "git
 274ls-tree", "git add", "git grep", "git diff", "git checkout",
 275and many other commands to
 276limit the scope of operations to some subset of the tree or
 277worktree.  See the documentation of each command for whether
 278paths are relative to the current directory or toplevel.  The
 279pathspec syntax is as follows:
 280
 281* any path matches itself
 282* the pathspec up to the last slash represents a
 283  directory prefix.  The scope of that pathspec is
 284  limited to that subtree.
 285* the rest of the pathspec is a pattern for the remainder
 286  of the pathname.  Paths relative to the directory
 287  prefix will be matched against that pattern using fnmatch(3);
 288  in particular, '*' and '?' _can_ match directory separators.
 289+
 290For example, Documentation/*.jpg will match all .jpg files
 291in the Documentation subtree,
 292including Documentation/chapter_1/figure_1.jpg.
 293
 294+
 295A pathspec that begins with a colon `:` has special meaning.  In the
 296short form, the leading colon `:` is followed by zero or more "magic
 297signature" letters (which optionally is terminated by another colon `:`),
 298and the remainder is the pattern to match against the path. The optional
 299colon that terminates the "magic signature" can be omitted if the pattern
 300begins with a character that cannot be a "magic signature" and is not a
 301colon.
 302+
 303In the long form, the leading colon `:` is followed by a open
 304parenthesis `(`, a comma-separated list of zero or more "magic words",
 305and a close parentheses `)`, and the remainder is the pattern to match
 306against the path.
 307+
 308The "magic signature" consists of an ASCII symbol that is not
 309alphanumeric.
 310+
 311--
 312top `/`;;
 313        The magic word `top` (mnemonic: `/`) makes the pattern match
 314        from the root of the working tree, even when you are running
 315        the command from inside a subdirectory.
 316--
 317+
 318Currently only the slash `/` is recognized as the "magic signature",
 319but it is envisioned that we will support more types of magic in later
 320versions of Git.
 321+
 322A pathspec with only a colon means "there is no pathspec". This form
 323should not be combined with other pathspec.
 324
 325[[def_parent]]parent::
 326        A <<def_commit_object,commit object>> contains a (possibly empty) list
 327        of the logical predecessor(s) in the line of development, i.e. its
 328        parents.
 329
 330[[def_pickaxe]]pickaxe::
 331        The term <<def_pickaxe,pickaxe>> refers to an option to the diffcore
 332        routines that help select changes that add or delete a given text
 333        string. With the `--pickaxe-all` option, it can be used to view the full
 334        <<def_changeset,changeset>> that introduced or removed, say, a
 335        particular line of text. See linkgit:git-diff[1].
 336
 337[[def_plumbing]]plumbing::
 338        Cute name for <<def_core_git,core Git>>.
 339
 340[[def_porcelain]]porcelain::
 341        Cute name for programs and program suites depending on
 342        <<def_core_git,core Git>>, presenting a high level access to
 343        core Git. Porcelains expose more of a <<def_SCM,SCM>>
 344        interface than the <<def_plumbing,plumbing>>.
 345
 346[[def_pull]]pull::
 347        Pulling a <<def_branch,branch>> means to <<def_fetch,fetch>> it and
 348        <<def_merge,merge>> it.  See also linkgit:git-pull[1].
 349
 350[[def_push]]push::
 351        Pushing a <<def_branch,branch>> means to get the branch's
 352        <<def_head_ref,head ref>> from a remote <<def_repository,repository>>,
 353        find out if it is a direct ancestor to the branch's local
 354        head ref, and in that case, putting all
 355        objects, which are <<def_reachable,reachable>> from the local
 356        head ref, and which are missing from the remote
 357        repository, into the remote
 358        <<def_object_database,object database>>, and updating the remote
 359        head ref. If the remote <<def_head,head>> is not an
 360        ancestor to the local head, the push fails.
 361
 362[[def_reachable]]reachable::
 363        All of the ancestors of a given <<def_commit,commit>> are said to be
 364        "reachable" from that commit. More
 365        generally, one <<def_object,object>> is reachable from
 366        another if we can reach the one from the other by a <<def_chain,chain>>
 367        that follows <<def_tag,tags>> to whatever they tag,
 368        <<def_commit_object,commits>> to their parents or trees, and
 369        <<def_tree_object,trees>> to the trees or <<def_blob_object,blobs>>
 370        that they contain.
 371
 372[[def_rebase]]rebase::
 373        To reapply a series of changes from a <<def_branch,branch>> to a
 374        different base, and reset the <<def_head,head>> of that branch
 375        to the result.
 376
 377[[def_ref]]ref::
 378        A 40-byte hex representation of a <<def_SHA1,SHA-1>> or a name that
 379        denotes a particular <<def_object,object>>. They may be stored in
 380        a file under `$GIT_DIR/refs/` directory, or
 381        in the `$GIT_DIR/packed-refs` file.
 382
 383[[def_reflog]]reflog::
 384        A reflog shows the local "history" of a ref.  In other words,
 385        it can tell you what the 3rd last revision in _this_ repository
 386        was, and what was the current state in _this_ repository,
 387        yesterday 9:14pm.  See linkgit:git-reflog[1] for details.
 388
 389[[def_refspec]]refspec::
 390        A "refspec" is used by <<def_fetch,fetch>> and
 391        <<def_push,push>> to describe the mapping between remote
 392        <<def_ref,ref>> and local ref. They are combined with a colon in
 393        the format <src>:<dst>, preceded by an optional plus sign, +.
 394        For example: `git fetch $URL
 395        refs/heads/master:refs/heads/origin` means "grab the master
 396        <<def_branch,branch>> <<def_head,head>> from the $URL and store
 397        it as my origin branch head". And `git push
 398        $URL refs/heads/master:refs/heads/to-upstream` means "publish my
 399        master branch head as to-upstream branch at $URL". See also
 400        linkgit:git-push[1].
 401
 402[[def_remote_tracking_branch]]remote-tracking branch::
 403        A regular Git <<def_branch,branch>> that is used to follow changes from
 404        another <<def_repository,repository>>. A remote-tracking
 405        branch should not contain direct modifications or have local commits
 406        made to it. A remote-tracking branch can usually be
 407        identified as the right-hand-side <<def_ref,ref>> in a Pull:
 408        <<def_refspec,refspec>>.
 409
 410[[def_repository]]repository::
 411        A collection of <<def_ref,refs>> together with an
 412        <<def_object_database,object database>> containing all objects
 413        which are <<def_reachable,reachable>> from the refs, possibly
 414        accompanied by meta data from one or more <<def_porcelain,porcelains>>. A
 415        repository can share an object database with other repositories
 416        via <<def_alternate_object_database,alternates mechanism>>.
 417
 418[[def_resolve]]resolve::
 419        The action of fixing up manually what a failed automatic
 420        <<def_merge,merge>> left behind.
 421
 422[[def_revision]]revision::
 423        A particular state of files and directories which was stored in the
 424        <<def_object_database,object database>>. It is referenced by a
 425        <<def_commit_object,commit object>>.
 426
 427[[def_rewind]]rewind::
 428        To throw away part of the development, i.e. to assign the
 429        <<def_head,head>> to an earlier <<def_revision,revision>>.
 430
 431[[def_SCM]]SCM::
 432        Source code management (tool).
 433
 434[[def_SHA1]]SHA-1::
 435        "Secure Hash Algorithm 1"; a cryptographic hash function.
 436        In the context of Git used as a synonym for <<def_object_name,object name>>.
 437
 438[[def_shallow_repository]]shallow repository::
 439        A shallow <<def_repository,repository>> has an incomplete
 440        history some of whose <<def_commit,commits>> have <<def_parent,parents>> cauterized away (in other
 441        words, Git is told to pretend that these commits do not have the
 442        parents, even though they are recorded in the <<def_commit_object,commit
 443        object>>). This is sometimes useful when you are interested only in the
 444        recent history of a project even though the real history recorded in the
 445        upstream is much larger. A shallow repository
 446        is created by giving the `--depth` option to linkgit:git-clone[1], and
 447        its history can be later deepened with linkgit:git-fetch[1].
 448
 449[[def_symref]]symref::
 450        Symbolic reference: instead of containing the <<def_SHA1,SHA-1>>
 451        id itself, it is of the format 'ref: refs/some/thing' and when
 452        referenced, it recursively dereferences to this reference.
 453        '<<def_HEAD,HEAD>>' is a prime example of a symref. Symbolic
 454        references are manipulated with the linkgit:git-symbolic-ref[1]
 455        command.
 456
 457[[def_tag]]tag::
 458        A <<def_ref,ref>> under `refs/tags/` namespace that points to an
 459        object of an arbitrary type (typically a tag points to either a
 460        <<def_tag_object,tag>> or a <<def_commit_object,commit object>>).
 461        In contrast to a <<def_head,head>>, a tag is not updated by
 462        the `commit` command. A Git tag has nothing to do with a Lisp
 463        tag (which would be called an <<def_object_type,object type>>
 464        in Git's context). A tag is most typically used to mark a particular
 465        point in the commit ancestry <<def_chain,chain>>.
 466
 467[[def_tag_object]]tag object::
 468        An <<def_object,object>> containing a <<def_ref,ref>> pointing to
 469        another object, which can contain a message just like a
 470        <<def_commit_object,commit object>>. It can also contain a (PGP)
 471        signature, in which case it is called a "signed tag object".
 472
 473[[def_topic_branch]]topic branch::
 474        A regular Git <<def_branch,branch>> that is used by a developer to
 475        identify a conceptual line of development. Since branches are very easy
 476        and inexpensive, it is often desirable to have several small branches
 477        that each contain very well defined concepts or small incremental yet
 478        related changes.
 479
 480[[def_tree]]tree::
 481        Either a <<def_working_tree,working tree>>, or a <<def_tree_object,tree
 482        object>> together with the dependent <<def_blob_object,blob>> and tree objects
 483        (i.e. a stored representation of a working tree).
 484
 485[[def_tree_object]]tree object::
 486        An <<def_object,object>> containing a list of file names and modes along
 487        with refs to the associated blob and/or tree objects. A
 488        <<def_tree,tree>> is equivalent to a <<def_directory,directory>>.
 489
 490[[def_tree-ish]]tree-ish::
 491        A <<def_ref,ref>> pointing to either a <<def_commit_object,commit
 492        object>>, a <<def_tree_object,tree object>>, or a <<def_tag_object,tag
 493        object>> pointing to a tag or commit or tree object.
 494
 495[[def_unmerged_index]]unmerged index::
 496        An <<def_index,index>> which contains unmerged
 497        <<def_index_entry,index entries>>.
 498
 499[[def_unreachable_object]]unreachable object::
 500        An <<def_object,object>> which is not <<def_reachable,reachable>> from a
 501        <<def_branch,branch>>, <<def_tag,tag>>, or any other reference.
 502
 503[[def_upstream_branch]]upstream branch::
 504        The default <<def_branch,branch>> that is merged into the branch in
 505        question (or the branch in question is rebased onto). It is configured
 506        via branch.<name>.remote and branch.<name>.merge. If the upstream branch
 507        of 'A' is 'origin/B' sometimes we say "'A' is tracking 'origin/B'".
 508
 509[[def_working_tree]]working tree::
 510        The tree of actual checked out files.  The working tree normally
 511        contains the contents of the <<def_HEAD,HEAD>> commit's tree,
 512        plus any local changes that you have made but not yet committed.