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commit is

A commit, or "revision", is an individual change to a file (or set of files). It's like when you save a file, except with Git, every time you save it creates a unique ID (a.k.a. the "SHA" or "hash") that allows you to keep record of what changes were made when and by who. Commits usually contain a commit message which is a brief description of what changes were made.

but i didn't got it

What is exactly meaning of commit in git and git hub?

NOTE:-This not dupli of any Q I am clear about git push

Pratik pound
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    "A commit is like a save or snapshot of your entire project." <— from the linked documentation – Arya McCarthy May 15 '17 at 01:59
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    Possible duplicate of [What are the differences between "git commit" and "git push"?](http://stackoverflow.com/questions/2745076/what-are-the-differences-between-git-commit-and-git-push) – Arya McCarthy May 15 '17 at 02:01
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    @aryamccarthy if i hit `ctrl` +`s` in editor then what is need of commit – Pratik pound May 15 '17 at 02:03
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    With git, a) it keeps track of all files as a group, and b) it's distributed. You and multiple people can handle the same set of files on multiple machines. – Arya McCarthy May 15 '17 at 02:11

5 Answers5

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After you do changes in your code you will do "commit".

Commit set a message about the changes you were done. The commit also saves a revision of the code and you can revert the code to any version anytime in one click.

All time the perfect example for this is like a tree. Source tree for more precisely. This will be the perfect to explain the git branch on the source tree:

Git Sourcetree

Every commit its a point on the "master", the master will be the tree trunk.

You can add a branch to the tree and add more commit only on this branch. After the changes, you can merge the change to the master.

So in summary, git is used as a code version manager. Knows how to deal with conflicts and combine several different versions into one version.

And this is screen capture of comparing two different code versions (commits)

comparing two different commits on PhpStorm IDE

Hope I helped you :)

Moshe Harush
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A commit is kind of 'object' in git, and identifies and specifies a 'snapshot' of the branch at the time of the commit.

an object is a file stored under .git/objects

eg: object e6f53bc19b182fed6cd580329747f93393504389 is a file stored at .git/objects/e6/f53bc19b182fed6cd580329747f93393504389

If the object is a commit, it records other objects that together specify the commit 'snapshot'.

Typically, the 'other objects' recorded in a commit is just two other objects - the parent commit of the current commit and the 'tree' object that specifies the actual files.

You can examine an object thus

$ git cat-file -p e6f53bc19b182fed6cd580329747f93393504389
tree 7cb95c95270b3f28a3cb6e2107f89dc7e950d93e
parent 507dbda38d769e8c69b3701cbd21a40b3a39206e
author xx <xx@xx.com> 1578053251 +0000
committer xx <xx@xx.com> 1578053251 +0000

my big commit message here!

That's it. A commit is a file stored in .git/objects that specifies a snapshot. It contains one or more references to the parent commits and a reference to a tree object.

There are 3 types of 'git object'

commit object: contains reference to commit objects and tree objects

tree object: contains references to 'blob' objects and tree objects

blob object: contains the file contents, a blob object usually represents a whole file.

Simon Clewer
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Commits are to software developers what checkpoints are to gamers.

In video games you can have many checkpoints (or save files). When something goes horribly wrong you can load a previous checkpoint and resume from there.

Let's say you're trying to fix a bug and changed some lines of code. If you realize that your change didn't work and broke some other part of the code, you could revert to a previous commit that you know was working correctly and try a different solution. Once you have a working solution, you can create a new commit with your change, and that gives you a new checkpoint to fallback on without being afraid of losing your progress.

After a while, you will have a history of all the changes in your code, represented by a series of commits telling you:

  • what the change was about
  • who made the change
  • when was the change made
  • a unique commit identifier

Example of a commit history:

example of a commit history

Example of a commit:

example of a commit

WebF0x
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(Yes, old question. But to help web searchers...)

One possible point of confusion is that, in git lingo, 'commit' is both a noun and a verb. From its glossary

As a noun: A single point in the Git history; the entire history of a project is represented as a set of interrelated commits. The word "commit" is often used by Git in the same places other revision control systems use the words "revision" or "version". Also used as a short hand for commit object.

As a verb: The action of storing a new snapshot of the project’s state in the Git history, by creating a new commit representing the current state of the index and advancing HEAD to point at the new commit.

(See https://git-scm.com/docs/gitglossary)

Community
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Loren Rosen
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The git commit command captures a snapshot of the project's currently staged changes. Committed snapshots can be thought of as “safe” versions of a project—Git will never change them unless you explicitly ask it to. Prior to the execution of git commit, The git add command is used to promote or 'stage' changes to the project that will be stored in a commit. These two commands git commit and git add are two of the most frequently used.

tech user
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