1object:: 2 The unit of storage in GIT. It is uniquely identified by 3 the SHA1 of its contents. Consequently, an object can not 4 be changed. 5 6object name:: 7 The unique identifier of an object. The hash of the object's contents 8 using the Secure Hash Algorithm 1 and usually represented by the 40 9 character hexadecimal encoding of the hash of the object (possibly 10 followed by a white space). 11 12SHA1:: 13 Synonym for object name. 14 15object identifier:: 16 Synonym for object name. 17 18hash:: 19 In git's context, synonym to object name. 20 21object database:: 22 Stores a set of "objects", and an individial object is identified 23 by its object name. The object usually live in $GIT_DIR/objects/. 24 25blob object:: 26 Untyped object, e.g. the contents of a file. 27 28tree object:: 29 An object containing a list of file names and modes along with refs 30 to the associated blob and/or tree objects. A tree object is 31 equivalent to a directory. 32 33tree:: 34 Either a working tree, or a tree object together with the 35 dependent blob and tree objects (i.e. a stored representation 36 of a working tree). 37 38index:: 39 A collection of files with stat information, whose contents are 40 stored as objects. The cache is a stored version of your working 41 tree. Truth be told, it can also contain a second, and even a third 42 version of a working tree, which are used when merging. 43 44index entry:: 45 The information regarding a particular file, stored in the index. 46 An index entry can be unmerged, if a merge was started, but not 47 yet finished (i.e. if the cache contains multiple versions of 48 that file). 49 50unmerged index: 51 An index which contains unmerged index entries. 52 53cache:: 54 Obsolete for: index. 55 56working tree:: 57 The set of files and directories currently being worked on, 58 i.e. you can work in your working tree without using git at all. 59 60directory:: 61 The list you get with "ls" :-) 62 63revision:: 64 A particular state of files and directories which was stored in 65 the object database. It is referenced by a commit object. 66 67checkout:: 68 The action of updating the working tree to a revision which was 69 stored in the object database. 70 71commit:: 72 As a verb: The action of storing the current state of the cache in the 73 object database. The result is a revision. 74 As a noun: Short hand for commit object. 75 76commit object:: 77 An object which contains the information about a particular 78 revision, such as parents, committer, author, date and the 79 tree object which corresponds to the top directory of the 80 stored revision. 81 82parent:: 83 A commit object contains a (possibly empty) list of the logical 84 predecessor(s) in the line of development, i.e. its parents. 85 86changeset:: 87 BitKeeper/cvsps speak for "commit". Since git does not store 88 changes, but states, it really does not make sense to use 89 the term "changesets" with git. 90 91clean:: 92 A working tree is clean, if it corresponds to the revision 93 referenced by the current head. 94 95dirty:: 96 A working tree is said to be dirty if it contains modifications 97 which have not been committed to the current branch. 98 99head:: 100 The top of a branch. It contains a ref to the corresponding 101 commit object. 102 103branch:: 104 A non-cyclical graph of revisions, i.e. the complete history of 105 a particular revision, which is called the branch head. The 106 branch heads are stored in $GIT_DIR/refs/heads/. 107 108ref:: 109 A 40-byte hex representation of a SHA1 pointing to a particular 110 object. These may be stored in $GIT_DIR/refs/. 111 112head ref:: 113 A ref pointing to a head. Often, this is abbreviated to "head". 114 Head refs are stored in $GIT_DIR/refs/heads/. 115 116tree-ish:: 117 A ref pointing to either a commit object, a tree object, or a 118 tag object pointing to a tag or commit or tree object. 119 120ent:: 121 Favorite synonym to "tree-ish" by some total geeks. See 122 http://en.wikipedia.org/wiki/Ent_(Middle-earth) for an in-depth 123 explanation. 124 125tag object:: 126 An object containing a ref pointing to another object, which can 127 contain a message just like a commit object. It can also 128 contain a (PGP) signature, in which case it is called a "signed 129 tag object". 130 131tag:: 132 A ref pointing to a tag or commit object. In contrast to a head, 133 a tag is not changed by a commit. Tags (not tag objects) are 134 stored in $GIT_DIR/refs/tags/. A git tag has nothing to do with 135 a Lisp tag (which is called object type in git's context). 136 A tag is most typically used to mark a particular point in the 137 commit ancestry chain. 138 139merge:: 140 To merge branches means to try to accumulate the changes since a 141 common ancestor and apply them to the first branch. An automatic 142 merge uses heuristics to accomplish that. Evidently, an automatic 143 merge can fail. 144 145resolve:: 146 The action of fixing up manually what a failed automatic merge 147 left behind. 148 149rewind:: 150 To throw away part of the development, i.e. to assign the head to 151 an earlier revision. 152 153rebase:: 154 To clean a branch by starting from the head of the main line of 155 development ("master"), and reapply the (possibly cherry-picked) 156 changes from that branch. 157 158repository:: 159 A collection of refs together with an object database containing 160 all objects, which are reachable from the refs, possibly accompanied 161 by meta data from one or more porcelains. A repository can 162 share an object database with other repositories. 163 164git archive:: 165 Synonym for repository (for arch people). 166 167file system:: 168 Linus Torvalds originally designed git to be a user space file 169 system, i.e. the infrastructure to hold files and directories. 170 That ensured the efficiency and speed of git. 171 172alternate object database:: 173 Via the alternates mechanism, a repository can inherit part of its 174 object database from another object database, which is called 175 "alternate". 176 177reachable:: 178 An object is reachable from a ref/commit/tree/tag, if there is a 179 chain leading from the latter to the former. 180 181chain:: 182 A list of objects, where each object in the list contains a 183 reference to its successor (for example, the successor of a commit 184 could be one of its parents). 185 186fetch:: 187 Fetching a branch means to get the branch's head ref from a 188 remote repository, to find out which objects are missing from 189 the local object database, and to get them, too. 190 191pull:: 192 Pulling a branch means to fetch it and merge it. 193 194push:: 195 Pushing a branch means to get the branch's head ref from a remote 196 repository, find out if it is an ancestor to the branch's local 197 head ref is a direct, and in that case, putting all objects, which 198 are reachable from the local head ref, and which are missing from 199 the remote repository, into the remote object database, and updating 200 the remote head ref. If the remote head is not an ancestor to the 201 local head, the push fails. 202 203pack:: 204 A set of objects which have been compressed into one file (to save 205 space or to transmit them efficiently). 206 207pack index:: 208 The list of identifiers, and other information, of the objects in a 209 pack, to assist in efficiently accessing the contents of a pack. 210 211core git:: 212 Fundamental data structures and utilities of git. Exposes only 213 limited source code management tools. 214 215plumbing:: 216 Cute name for core git. 217 218porcelain:: 219 Cute name for programs and program suites depending on core git, 220 presenting a high level access to core git. Porcelains expose 221 more of a SCM interface than the plumbing. 222 223object type: 224 One of the identifiers "commit","tree","tag" and "blob" describing 225 the type of an object. 226 227SCM:: 228 Source code management (tool). 229 230dircache:: 231 You are *waaaaay* behind. 232