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.
In git's context, synonym to object name.
object database::
- Stores a set of "objects", and an individial object is identified
- by its object name. The object usually live in $GIT_DIR/objects/.
+ Stores a set of "objects", and an individual object is identified
+ by its object name. The objects usually live in `$GIT_DIR/objects/`.
blob object::
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).
+ 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).
+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 cache is a stored version of your working
+ 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.
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 cache contains multiple versions of
+ yet finished (i.e. if the index contains multiple versions of
that file).
unmerged index:
stored in the object database.
commit::
- As a verb: 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.
As a noun: Short hand for commit object.
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 $GIT_DIR/refs/heads/.
+ branch heads are stored in `$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
- object. These may be 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 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
tag object pointing to a tag or commit or tree object.
ent::
- Favorite synonym to "tree-ish" by some total geeks.
+ 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::
- 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
- 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 tag is most typically used to mark a particular point in the
commit ancestry chain.
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.
+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
all objects, which are reachable from the refs, possibly accompanied
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.