1alternate object database:: 2 Via the alternates mechanism, a repository can inherit part of its 3 object database from another object database, which is called 4 "alternate". 5 6blob object:: 7 Untyped object, e.g. the contents of a file. 8 9branch:: 10 A non-cyclical graph of revisions, i.e. the complete history of 11 a particular revision, which is called the branch head. The 12 branch heads are stored in `$GIT_DIR/refs/heads/`. 13 14cache:: 15 Obsolete for: index. 16 17chain:: 18 A list of objects, where each object in the list contains a 19 reference to its successor (for example, the successor of a commit 20 could be one of its parents). 21 22changeset:: 23 BitKeeper/cvsps speak for "commit". Since git does not store 24 changes, but states, it really does not make sense to use 25 the term "changesets" with git. 26 27checkout:: 28 The action of updating the working tree to a revision which was 29 stored in the object database. 30 31clean:: 32 A working tree is clean, if it corresponds to the revision 33 referenced by the current head. Also see "dirty". 34 35commit:: 36 As a verb: The action of storing the current state of the index in the 37 object database. The result is a revision. 38 As a noun: Short hand for commit object. 39 40commit object:: 41 An object which contains the information about a particular 42 revision, such as parents, committer, author, date and the 43 tree object which corresponds to the top directory of the 44 stored revision. 45 46core git:: 47 Fundamental data structures and utilities of git. Exposes only 48 limited source code management tools. 49 50DAG:: 51 Directed acyclic graph. The commit objects form a directed acyclic 52 graph, because they have parents (directed), and the graph of commit 53 objects is acyclic (there is no chain which begins and ends with the 54 same object). 55 56dircache:: 57 You are *waaaaay* behind. 58 59dirty:: 60 A working tree is said to be dirty if it contains modifications 61 which have not been committed to the current branch. 62 63directory:: 64 The list you get with "ls" :-) 65 66ent:: 67 Favorite synonym to "tree-ish" by some total geeks. See 68 `http://en.wikipedia.org/wiki/Ent_(Middle-earth)` for an in-depth 69 explanation. 70 71fetch:: 72 Fetching a branch means to get the branch's head ref from a 73 remote repository, to find out which objects are missing from 74 the local object database, and to get them, too. 75 76file system:: 77 Linus Torvalds originally designed git to be a user space file 78 system, i.e. the infrastructure to hold files and directories. 79 That ensured the efficiency and speed of git. 80 81git archive:: 82 Synonym for repository (for arch people). 83 84hash:: 85 In git's context, synonym to object name. 86 87head:: 88 The top of a branch. It contains a ref to the corresponding 89 commit object. 90 91head ref:: 92 A ref pointing to a head. Often, this is abbreviated to "head". 93 Head refs are stored in `$GIT_DIR/refs/heads/`. 94 95index:: 96 A collection of files with stat information, whose contents are 97 stored as objects. The index is a stored version of your working 98 tree. Truth be told, it can also contain a second, and even a third 99 version of a working tree, which are used when merging. 100 101index entry:: 102 The information regarding a particular file, stored in the index. 103 An index entry can be unmerged, if a merge was started, but not 104 yet finished (i.e. if the index contains multiple versions of 105 that file). 106 107master:: 108 The default branch. Whenever you create a git repository, a branch 109 named "master" is created, and becomes the active branch. In most 110 cases, this contains the local development. 111 112 113merge:: 114 To merge branches means to try to accumulate the changes since a 115 common ancestor and apply them to the first branch. An automatic 116 merge uses heuristics to accomplish that. Evidently, an automatic 117 merge can fail. 118 119object:: 120 The unit of storage in git. It is uniquely identified by 121 the SHA1 of its contents. Consequently, an object can not 122 be changed. 123 124object database:: 125 Stores a set of "objects", and an individual object is identified 126 by its object name. The objects usually live in `$GIT_DIR/objects/`. 127 128object identifier:: 129 Synonym for object name. 130 131object name:: 132 The unique identifier of an object. The hash of the object's contents 133 using the Secure Hash Algorithm 1 and usually represented by the 40 134 character hexadecimal encoding of the hash of the object (possibly 135 followed by a white space). 136 137object type: 138 One of the identifiers "commit","tree","tag" and "blob" describing 139 the type of an object. 140 141octopus:: 142 To merge more than two branches. Also denotes an intelligent 143 predator. 144 145origin:: 146 The default upstream branch. Most projects have one upstream 147 project which they track, and by default 'origin' is used for 148 that purpose. New updates from upstream will be fetched into 149 this branch; you should never commit to it yourself. 150 151pack:: 152 A set of objects which have been compressed into one file (to save 153 space or to transmit them efficiently). 154 155pack index:: 156 The list of identifiers, and other information, of the objects in a 157 pack, to assist in efficiently accessing the contents of a pack. 158 159parent:: 160 A commit object contains a (possibly empty) list of the logical 161 predecessor(s) in the line of development, i.e. its parents. 162 163plumbing:: 164 Cute name for core git. 165 166porcelain:: 167 Cute name for programs and program suites depending on core git, 168 presenting a high level access to core git. Porcelains expose 169 more of a SCM interface than the plumbing. 170 171pull:: 172 Pulling a branch means to fetch it and merge it. 173 174push:: 175 Pushing a branch means to get the branch's head ref from a remote 176 repository, find out if it is an ancestor to the branch's local 177 head ref is a direct, and in that case, putting all objects, which 178 are reachable from the local head ref, and which are missing from 179 the remote repository, into the remote object database, and updating 180 the remote head ref. If the remote head is not an ancestor to the 181 local head, the push fails. 182 183reachable:: 184 An object is reachable from a ref/commit/tree/tag, if there is a 185 chain leading from the latter to the former. 186 187rebase:: 188 To clean a branch by starting from the head of the main line of 189 development ("master"), and reapply the (possibly cherry-picked) 190 changes from that branch. 191 192ref:: 193 A 40-byte hex representation of a SHA1 pointing to a particular 194 object. These may be stored in `$GIT_DIR/refs/`. 195 196repository:: 197 A collection of refs together with an object database containing 198 all objects, which are reachable from the refs, possibly accompanied 199 by meta data from one or more porcelains. A repository can 200 share an object database with other repositories. 201 202resolve:: 203 The action of fixing up manually what a failed automatic merge 204 left behind. 205 206revision:: 207 A particular state of files and directories which was stored in 208 the object database. It is referenced by a commit object. 209 210rewind:: 211 To throw away part of the development, i.e. to assign the head to 212 an earlier revision. 213 214SCM:: 215 Source code management (tool). 216 217SHA1:: 218 Synonym for object name. 219 220tree object:: 221 An object containing a list of file names and modes along with refs 222 to the associated blob and/or tree objects. A tree is equivalent 223 to a directory. 224 225tree:: 226 Either a working tree, or a tree object together with the 227 dependent blob and tree objects (i.e. a stored representation 228 of a working tree). 229 230tree-ish:: 231 A ref pointing to either a commit object, a tree object, or a 232 tag object pointing to a tag or commit or tree object. 233 234tag object:: 235 An object containing a ref pointing to another object, which can 236 contain a message just like a commit object. It can also 237 contain a (PGP) signature, in which case it is called a "signed 238 tag object". 239 240tag:: 241 A ref pointing to a tag or commit object. In contrast to a head, 242 a tag is not changed by a commit. Tags (not tag objects) are 243 stored in `$GIT_DIR/refs/tags/`. A git tag has nothing to do with 244 a Lisp tag (which is called object type in git's context). 245 A tag is most typically used to mark a particular point in the 246 commit ancestry chain. 247 248unmerged index: 249 An index which contains unmerged index entries. 250 251working tree:: 252 The set of files and directories currently being worked on, 253 i.e. you can work in your working tree without using git at all. 254